Lab Report Identifying Food Groups
ups Identifying food groups in unknown solutions
Aim
The aim of this experiment is to identify different food groups within several different unknown solutions. This will be carried out by placing the unknown solutions into separate test tubes and using different chemical indicators to see if any reactions occur. Each food group will act different when the chemical indicator is added, some will change colour while others will separate.
Introduction
Food is a vital source of energy that is needed for survival, without this energy source our bodies wouldn’t be able to function. All food can be broken down into various food groups such as water, proteins, carbohydrates, vitamins, fats, fibre and minerals. Our bodies need all of these food groups to function with each of them playing a specific role. These food groups are present in our every day food and are taken into our body through a process of digestion. The food is chewed up and broken down into smaller bits in the mouth and then travels down to the stomach where it is broken down further by the hydrochloric acid in the stomach in a process called chemical digestion. Once the food has been broken down it is then absorbed by the blood to provide the various functions that our body needs to survive. We can get some of these food groups by other means such as vitamin injections, tablets …show more content…
or food supplements. These are generally taken when our bodies are not able to break down certain foods down, have allergies or vegetarians.
There are many different ways we can test food for the presence of certain substances within the food we eat. To test for carbohydrates or sugar in food a liquid called Benedict’s reagent is used, Benedict’s reagent contains sodium citrate, sodium carbonate and copper sulphate. Benedict’s reagent is mixed with a sample of food and then heated, if any reducing sugars such as glucose are present it will produce a precipitate. Depending on the amount of reducing sugar present the colour will change from yellow to brick red, the darker the precipitate goes the more concentration of sugar is in the food. This can be used to test for diabetes, by testing for sugar in the urine.
More complex sugars such as starch can be tested for by using iodine, starch has a helix configuration with enough dimensions to accommodate the iodine molecules which in turn interact with the glucose molecules in the starch. When starch is present the the liquid will turn a blue-black colour indication the presence of starch.
The test for proteins is known as the Biuret test, this uses a combination of sodium hydroxide and copper sulphate mixing them with the food will produce a colour change from blue, pink, lilac or violet depending on the concentration of proteins present.
Lipids are characterised by their insoluble nature in water so to test for the presence of lipids a organic solvent called ethanol (meths) is used. When the unknown solution and ethanol is mixed together and diluted with a small amount of water. The presence of lipids will give a white cloudy like emulsion.
To test for the presence of vitamin C a blue dye called DCPIP is used, the dye will lose its colour when in the presence of vitamin C (but not for other vitamins which are composed of different chemicals).
There are many reasons why we need to know the presence of different substances in food, foods high in sugar may be a vital source of energy but not taken in proportion can lead to health problems such as obesity and diabetes, excess amounts of lipids in food can lead to high cholesterol which may cause heart problems, proteins are important in our diet as they act as a catalyst for the chemical reactions that occur in our bodies, vitamin C helps maintain strong bones and good eyesight. To know what is in our food helps to moderate what we eat providing us with all the nutrition we need for a healthy body.
Materials and methods
Materials * Test tube rack * Test tubes * Beaker * Pipette * Boiled water * Filter paper * Benedict’s solution * Iodine * 2M sodium hydroxide * 1% copper sulphate * `Ethanol * Water * DCPIP solution 0.1% Methods
Method for Benedict’s test for reducing sugars. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknow solution added from the corresponding bottles using a pipette. * A measurement of 2 cm3 of Benedict’s solution was added to each of the test tubes using a pipette. * A beaker was filled with boiled water. * All the five test tubes were placed in the beaker with the boiled water for five minutes. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the iodine test for starch. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknow solution added from the corresponding bottles using a pipette. * A measurement of 4 drops of iodine solution was added to each of the test tubes. * The test tubes were left for 2 minutes. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the Biuret test for proteins. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknown solution added from the corresponding bottles using a pipette. * A measurement of 2cm3 of 2M sodium hydroxide was added to each of the test tubes. * Each test tube was shaken gently to mix the solutions. * A measurement of four drops of 1% copper sulphate was slowly added to the test tubes one drop a time. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the emulsion and paper tests for lipids.
Emulsion test * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E. * A measurement of 2cm3 of ethanol (meths) was added to each of the test tubes. * A measurement of 2cm3 of the corresponding unknown solution was added to each of the test tubes. * The top of each of the test tubes were covered with Parafilm and gently shaken. * A measurement of 5 drops of water was added to each of the test tubes. * The top of each of the test tubes were covered with Parafilm and gently shaken. * The test tubes were observed for two minutes and the results were recorded in a table.
Paper test * A piece of filter paper was used. * The filter paper was divided into five sections. * Each section was labelled A-E to correspond with the unknown solution * A measurement of two drops of each of the unknown solutions was placed on the filter paper. * The filter paper was observed after five minutes and after ten minutes and the results were recorded in a table.
Method for the DCPIP test for vitamin C * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E. * A measurement of 2cm3 of 0.1% DCPIP solution was added to each of the test tubes. * A measurement of 2cm3 of each of the unknown solutions was slowly added drop by drop to each of the corresponding test tubes. * The test tubes were observed for two minutes and the results were recorded in a table.
Table of results for Benedict’s solution test for reducing sugars. solution | Positive/Negative reaction for reducing sugar | Original colour | Colour change | A | Negative | Cloudy White translucent | Yes, turned light blue translucent | B | Positive | Clear, translucent | Yes, turned dark orange | C | positive | White, milky | Yes, turned yellow | D | Positive | Cloudy grey/black translucent | Yes, turned dark orange | E | Negative | Gold, rich oily | No | The test for reducing sugars provided two positive results, both unknown solutions A and D turned dark orange in colour confirming presence of vitamin A. Unknown solution C turned yellow in colour which indicated a very low presence of reducing sugar.
Table of results of iodine test for Starch. solution | Positive/Negative reaction for starch | Original colour | Colour change | A | Positive | Cloudy White translucent | Yes, turned charcoal-black | B | Negative | Clear, translucent | No | C | Negative | White, milky | No | D | Negative | Cloudy grey/black translucent | No | E | Negative | Gold, rich oily | No |
Unknown solution A tested positive for the presence of starch, with none of the other unknown solutions having any colour change reactions.
Table of results of Biuret test for proteins. solution | Positive/Negative results for proteins | Original colour | Colour change | A | Negative | Cloudy White translucent | Yes, slight blue tint | B | Negative | Clear, translucent | No | C | Positive | White, milky | Yes, turned purple | D | Negative | Cloudy grey/black translucent | Yes, turned bright yellow | E | Negative | Gold, rich oily | No |
Unknown solution C tested positive for the presence of proteins with two of the other solutions having a reaction but negative for the presence of proteins.
Table of results for emulsion test for Lipids. solution | Positive/Negative reaction for lipids | Original colour | Colour change | A | Negative | Cloudy White translucent | No | B | Negative | Clear, translucent | No | C | Negative | White, milky | No | D | Negative | Cloudy grey/black translucent | No | E | Positive | Gold, rich oily | Yes, turned milky white and cloudy |
Unknown solution E tested positive for the presence of the lipids, turning a cloudy milky white colour with none of the other solutions having any positive results or colour changes.
Table of results for DCPIP test for Vitamin C. solution | Positive/Negative reaction for vitamin C | Original colour | Colour change | A | Negative | White | No | B | Negative | Clear, translucent | No | C | Negative | White | No | D | Positive | Cloudy grey/black translucent | Yes, clear with a slight gold tint | E | Negative | gold | No |
Unknown solution D tested positive for the presence of vitamin C with none of the other unknown solutions having any positive reactions or colour changes
Summary
After the completion of the test all five unknown solutions were identified as labelled below.
Solution A - starch
Solution B – reducing sugar
Solution C – protein
Solution D – vitamin C
Solution E – Lipids
The test to identify a number of food groups in unknown solutions provided positive results with all the unknown solutions being clearly identified. The test for reducing sugars provided two positive results, both solutions B and D turned dark orange. This was the result of a vitamin C tablet being used in the unknown solution D which contains a small amount of reducing sugar. Some of unknown food groups reacted with the solutions changing the colour and appearance but did not provide positive results as the changes did not correspond with the specific colour needed to confirm the presence of the unknown foods.
Conclusion
After completion of the experiment all five unknown foods were identified correctly, the methods used provided positive results. The test for reducing sugars provided two results with the unknown foods B and D testing positive this was due to the unknown food in test tube D being a vitamin E tablet which contains a small amount of reducing sugar. Although the test provided positive results improvements could be made for future experiments. A more pure source of vitamin A should be used the next time this would eliminate any chance of having two positive results for the reducing sugars. More foods could of been used containing different amounts of protein this would of provided varied results showing the different colours from yellow to dark orange and the different concentrations each food contained.
The unknown food containing the lipids portrayed a specific trend, when mixed with the various solutions it formed a layer above the solution keeping the solution at the bottom. From the way the lipids behaved due to them being hydrophobic it was possible to hypothesize that the unknown food was the lipids before it was mixed with ethanol. The paper test for the lipids also provided positive results with the rest of the unknown foods drying into the paper while the lipids left a translucent mark.
Overall the experiment was very successful, if the experiment was to be repeated more unknown foods could be used of both solid and liquid forms. This would provide different forms of concentration when tested giving a more varied set of results. Foods could be used that contain more than one of the food groups and too try and identify what the food is.
The structure of proteins
Proteins are one of the most structural complex macromolecules in biochemistry and make up over 50% of the dry mass of a cell.
Each protein is made up of a linear chain of amino acids linked together by peptide bonds (all peptide bonds are covalent bonds). The amount of amino acids bonded together can vary from tens too thousands, creating different proteins. There are 20 different amino acids in living organisms and the combination of these amino acids linked together in different polypeptide chains can result in trillions of different combinations of chains creating many different proteins (proteincrystallography,
2012).
Amino acids can be split into two groups, the basic amino group (-NH2) and the acidic carboxyl group (-COOH) the combination of these creating amino acids, as the amino acids have both a base and a acid present it is said to be amphoteric. All amino acids contain carbon, oxygen, hydrogen and nitrogen with some containing sulphur as well. The two groups are linked to each other by the same carbon atom. The diagram below shows one of the simpler amino acids glycine.
-NH2 and -COOH groups linked by a carbon atom. (winona, 2012)
The rest of the amino acid is made up by a side chain represented by the H in the diagram above. Whilst all amino acids have the same basic structure, they all differ in character. The difference comes from the side chains in the groups. Some have extra carboxyl groups while others have extra amino groups and the structure and layout being different for each amino acid polypeptide chain (advanced biology, 2012).
Amino acids are monomers of protein, monomers are molecules that can join together to form larger chains known as polymers (thefreedictionary, 2012). In proteins the amino acids are joined together by bonds called ‘peptide bonds’. The peptide bonds are formed when the amino group of one of the amino acids reacts with the acidic carboxyl group of another neighbouring amino acid linking them together, creating the peptide bond (-CONH). An example of a dipeptide bond forming is detailed in the diagram below. When the carboxyl group from one amino acid glycine bonds with an amino group from a alanine amino acid creating the bond. The bond can be completely different if the opposite groups are used from the amino acids.
Two different formations of amino acids bonding
Alanyl-glycine glycine-alanyl (Chemspider, 2012) When the two amino acids join together it causes a loss of water (H2O) known as a condensation reaction (advanced biology, 2012). Polypeptide chains will be formed by amino acid residue (during to the formation of the chains, water is lost so the peptide chains are made up from the remaining biochemical’s or the ‘the amino acid residue’). The joining of two amino acids is known as a dipeptide chain, three amino acids is known as a tripeptide chain while any more is known as a polypeptide chain. Once the polypeptide chain has reached 50 plus amino acids it is then regarded as a protein.
The peptide bonds formed and the polypeptide chain (Molecularsciences, 2012)
The structure of a protein can be split into four different groups, the primary structure, secondary structure, tertiary structure and quaternary structure. The four different groups of the structure of a protein show how the amino acids form from their original peptide bonds to evolve into large complex molecular structures. The amino acids form these complex three dimensional structures is all controlled from the very start by the coded DNA in the nucleus. Proteins relay heavily on the shape that is created within the coding of these three dimensional structures, the majority of proteins are enzymes which help catalyse biochemical reactions in the body. Without the specific shapes of the active site of an enzyme it would not be able to react with the substrate molecules (protein structure, 2012).
Lock and key model
-The primary structure of a protein relates to the number of amino acids and the sequence they are held together by the Amino acids that link together to form the polypeptide chains peptide bonds in the polypeptide chains, this is controlled by the DNA coding within the chromosomes in the nucleus. If one amino acid is altered during the formation of the sequence it can alter the properties of the protein completely.
(Neb, 2012) The alpha helix and the beta sheet -The secondary structure of a protein involves the polypeptide chain starting to take shape or folding up, this is the result of the hydrogen bonding which plays an important role in stabilizing the folding patterns. There are two very distinct formations of the secondary structure. The alpha (α) helix and the beta (β) pleated sheet. The alphas helix is a coiled or spiral in shape while the beta is flat like a sheet of paper. The hydrogen bonds keep the structures in shape. Most proteins will have a combination of both of these structures.
(Samford, 2012) Tertiary structure of alpha helix and beta sheets The tertiary structure starts to develop its complex three dimensional globular structure, the atoms are arranged within a single polypeptide chain unique to that protein. The tertiary structure comes about when the molecules are further folded and are held together in there complex shape by a combination of four different types of bonds. Hydrogen bonds which are relatively weak but help to stabilize the protein molecules, ionic bonds which relay on electrostatic interaction between the oppositely charged ions, disulphide bonds are formed between two cysteine amino acids that are found together, a strong double bond (ccbcmd.edu, 2012) will form between the sulphur atoms within the cysteine monomers (S=S) and Van Der Waals bonds. Some proteins are complete at this stage.
Where two Cysteine amino acids are found together, a strong double bond (S=S) is formed between the Sulphur atoms within the Cysteine monomers.
Bonds formed in a quandary structure The quandary structure
The quaternary structure is composed of multiply subunits of polypeptide chains linked together forming a complex molecule. The polypeptide chains are mainly held together by a form of hydrophobic interactions. When the polypeptide chains fold into a three dimensional shape it exposes its polar sides to an aqueous environment and shielding its non-polar side chains. Some hydrophobic sections are still left exposed, these sections will then link up with exposed chains from other polypeptide chains creating the quandary structure, and a mixture of non-covalent bonds will also hold the complex shape in place (alevelnotes, 2012) An example of a quandary structure diagram of a hemoglobin protein is a hemoglobin protein which has four polypeptide chains linked together, two alpha (α) polypeptide chains and two beta (β) polypeptide chains around an inorganic prosthetic haem group. The purpose of the hemoglobin protein is to carry oxygen around in the blood, with the use of the haem group which contains positive iron ions (Fe2+) which binds to the oxygen.
(myweb, 2012)
Proteins can be classified in many different ways and can be split into different groups, each group of protein provides a different and vital role in our body with some of the proteins sharing similar properties.
Enzymes
* Catalyze chemical and biochemical reactions * Contains the biggest group of proteins * Responsible for all metabolic reactions in our cells * Involved in DNA and RNA * Hexokinase is a protein enzyme
Hormones
* Responsible for regulation of processes in organisms * Are small in size * Insulin is a protein hormone
Transport hormones * Transportation of ions and chemical compounds in the body * Insulin is a protein hormone * Haemoglobin is a transport hormone
Immunoglobulin or antibodies * Neutralize foreign molecules in the body such as infection * Antibodies can act as enzymes * Fibrin is a immunoglobulin protein
Structural proteins * Maintain structures of other biological components * Formation of the the organisms of the body * Collagen is a structural protein
Motor proteins * Convert chemical energy into mechanical energy * Responsible for muscular motion * Actin is a motor protein
Receptors
* Responsible for signal detection and translation * Rhodopsin is a receptor protein
Signaling proteins * Involved in the signaling translation process * Have properties of enzymes * GTPases is a signaling protein
Storage proteins * Contain energy released during metabolism processes * Ovalbumin is a storage protein
(Proteincrystallography, 2012)
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The structure of carbohydrates
Carbohydrates also known as carbs are an important part of our daily diet, they provide a vital energy source for the body. A certain amount of carbs is needed for the body to function properly and without this in our daily diet we can suffer from problems such as muscle cramps, fatigue and poor mental functions. Carbohydrates can be broke down into two groups simple carbohydrates, or monosaccharide’s and Classification of different forms of sugars complex carbohydrates, or polysaccharides. Simple carbohydrates are more easily digested by the body giving a brief energy boost and are found in a lot of processed foods, candy bars, white rice and white bread. Complex carbohydrates take a lot longer for the body digest this also results in a more sustained level of energy for the body compared to simple carbs, foods such as brown bread, brown rice, oatmeal, potatoes and pasta contain complex carbohydrates (wisegeek, 2012).
Carbohydrates are the biggest group of organic compounds found in all living things. (fao, 2012) All carbohydrates can be broke down into three elements, hydrogen, oxygen and nitrogen with the ratio of 2:1 between hydrogen and oxygen the same as in water and can be represented by the general formula Cx(H2O)y . Simple carbohydrates or monosaccharide’s are made up of single sugar units and sweet tasting such as glyceraldehydes, glucose, ribose, fructose, mannose and galactose. These are the building blocks or monomers Isomer of glucose of the more complex carbohydrates. The best known of these would be glucose which has the chemical symbol C6H12O6 or also known as a hexose sugar as it contains six carbon atoms. Almost all naturally occurring sugars found in carbohydrates are isomers as each individual sugar can have different arrangements of the same chemical formula.
Disaccharides form when two monosaccharide’s bond together by a glycosidic bond. The glycosidic bonds are covalent bonds between the adjoining –OH groups of the sugar, when the bond forms between the two molecules it produce a loss of water called a condensation reaction. The covalent bond between the two molecules allows the body to break down the bonds easily creating energy. When glucose and glucose are bonded together it results in the formation of maltose. Some other combinations of disaccharide bonds are glucose + fructose which make sucrose and glucose + galactose which make Lactose.
Complex carbohydrates or Polysaccharides are formed by the joining of many monosaccharides linked together a glycosidic bond. A glycosidic bond is a type of covalent bond the joins two monosaccharides together, this takes place between the terminal end and the reducing ends of the sugar (the reducing end being towards the carbon atom in the molecule and the terminal being at the opposite end). This linkage produces a dehydration reaction where a molecule of water is released, the condensation is known as the Fisher glycosidation. This process can be reversed by a process of hydrolysis in which water is added to break the sugar down (Swarthmore, 2012). The more complex the sugar the harder it is to break down, thus being the reason why simple sugars give quick energy bursts while the more complex polysaccharide chains give longer lasing energy. if any excess sugar remains in the blood after it is broken down it is removed by the pancreas by the hormone insulin and stored in the liver and muscles as glycogen, this can then be broken down again into glucose when required by the body. Starch is a form of a complex sugar which is used by plants to store energy and when eaten by animals is then turned into glycogen.
The structure of lipids
The biochemical group for lipids includes fats, waxes and oils and contains the elements carbon, hydrogen and oxygen similar to carbohydrates but containing less oxygen. Lipids are hydrophobic molecules and can only be dissolved hydrocarbon tail of a triglyceride in organic solvents such as ethanol, propanone and ether. Unlike proteins and carbohydrates the monomers for lipids are made up of two different base units, fatty acids (monocarboxylic acids) and an alcohol called glycerol in a covalent bond called a ester bond in the ratio of 3:1 making triglyceride by a dehydration synthesis. (Proprofs, 2012
Lipids have hydrophobic properties due to the hydrocarbon tails containing somewhere between 14 and 22 carbon atoms surrounded by hydrogen atoms and are generally described as fatty acids as the –COOH group tends to slightly ionise to produce hydrogen ions which is the same property as acids. Fats and oils are both formed this way with one of the differences being oils are liquid while fats are solid at room temperature (advanced biology, 2012).
Fats and oils can be described as saturated and unsaturated depending on how they are bonded together. Fats (saturated) have all single bonds between the carbon and hydrogen atoms in the tail, this means that the carbon atoms can bond to the maximum amount of hydrogen atoms possible. The hydrocarbon tails are straight and the atoms can pack closely together making saturated fats solid at room temperature. (nature, 2012)
Oils (unsaturated) unlike fats have some double bonds in the tails causing kinks in the shape of the molecule, due to these double bonds between the carbons they can’t bond with as many of the hydrogen molecules, this in turn means the unsaturated fat cant pack as closely together making them an oil at room temperature, oils with more than one double bond are called polyunsaturated (Biology.clc.uc, 2012).
Lipids like carbohydrates and proteins can be split into different categories, with each category providing different functions within the body. All lipids share similar characteristics such as they are insoluble in water and a provide a high source of energy, the energy is harder to be released into the body due to insoluble nature so they are not a readily available energy source.
Phospholipids differ from triglyceride in they have two fatty acid chains and a phosphate group linked to a glycerol group. Phospholipids are mainly found in the membranes of cells due to them having both hydrophobic and hydrophilic properties. The phospholipids have the hydrophilic properties due to the phosphate group which is ionised making it negatively charged and attract water molecules. Phospholipids having both these properties help them regulate what molecules come in and out of a cell.
Glycolipids are molecules that contain single sugar units such as galactose or glucose. Glycolipids can range from having one sugar unit or more complex containing up to seven sugar molecules. Glycolipids can be found in the nerve cells and are used as a marker for cellular recognition and provide energy for cells.
Cholesterol consists of four hydrogen rings attached to a hydroxyl-hydrogen bond to oxygen group, cholesterol is also known as a steroid with the hydroxyl group providing it with amphipathic properties of being a hydrophobic and hydrophilic. Cholesterol is found in the blood and is not soluble. Due to cholesterol not being soluble it is carried to the cells via the help of lipoproteins. Too much cholesterol can be dangerous for the body but plays a vital role in in the cell membrane and works in conjunction with steroids.
Waxes are esters that are formed from more complex alcohols than glycerol along with fatty acids. Some of the uses of waxes occur mostly in plants but do occur in some animals providing a waterproof and protecting coating due to the hydrophobic properties (livestrong, 2012).
Human dietary requirements
To maintain a healthy body we must have a balanced diet, too little or too much of certain types of foods can have an adverse affect on the body causing defects, malnutrition or even death. To achieve a balanced diet we must take in all the required amounts of nutrition in a proportioned amount. We receive our nutrition from digesting food, the food is then broken down by the body to molecules small enough to be absorbed by the blood and then transported to where it is needed in the body. Nutrition provides energy to maintain the functions of the body such as strong bones, good eyesight, healthy skin, healthy organs and the ability of the body to repair itself. Some of the main dietary requirements needed by the body are proteins, carbohydrates, lipids, water, minerals and vitamins.
-Proteins are an important part of our daily diet, as all the cells in the human body contain protein and it makes up about 16% of our total body weight a daily intake is essential. When protein is digested into the body it is broken down into the different amino acids and absorbed into the blood and is part of some of the important chemicals within the body such as enzymes, hormones, neurotransmitters and DNA. The recommended daily intake (RDI) of protein can vary due to age or gender and whether you’re fit or pregnant. The RDI of protein is labelled below in the table and is worked out by multiplying the body weight of a person in kg by 0.8.
RDI of protein Weight in kilograms | Protein per day if you're not very active
(kg multiplied by 0.8) | Protein per day if you're active or pregnant
(kg multiplied by 1.3) | Protein per day if you're extremely active or in training
(kg multiplied by 1.8) | 45.5 kg | 36.4 g | 59.2 g | 81.9 g | 47.7 kg | 38.2 g | 62 g | 85.9 g | 50 kg | 40 g | 65 g | 90 g | 52.3 kg | 41.8 g | 68 g | 94.1 g | 54.5 kg | 43.6 g | 70.9 g | 98.1 g | 56.8 kg | 45.4 g | 73.8 g | 102.2 g | 59.1 kg | 47.3 g | 76.8 g | 106.4 g | 61.4 kg | 49.1 g | 79.8 g | 110.5 g | 63.6 kg | 50.9 g | 82.7 g | 114.5 g | 65.9 kg | 52.7 g | 85.7 g | 118.6 g | 68.2 kg | 54.7 g | 88.7 g | 122.8 g | 70.5 kg | 56.4 g | 91.7 g | 126.9 g | 72.7 kg | 58.2 g | 94.5 g | 130.8 g | 75 kg | 60 g | 97.5 g | 135 g |
(Fitsugar,2012)
A daily intake of protein is essential for the growth of hair, muscle, skin and connective tissue in our bodies and although our bodies are good at recycling protein we still need a constant supply to maintain a healthy life style. Some of the foods that are essential in maintaining this balanced diet are meat, eggs and dairy products which contain all the 20 amino acids available. Protein deficiencies tend to be rare if the right foods are ate, even with vegetarians and vegans such foods as soya milk, oatmeal, lima beans and spinach can be high sources of protein with all the amino acids required (lowcarbdiets.about, 2012).
An insufficient diet of protein can have some serious negative effects on the body.
Hair and skin * Hair will become brittle leading to alopecia or hair loss. * Wounds will take longer to heal. * Skin will undergo changes in pigmentation leading to dermatitis or pressure ulcers.
Muscles and growth * Muscle wasting and weakness resulting in a loss of muscle mass leading to protein deficiency disease called ‘marasmus’. * Insufficient protein in babies/children can led to problems in gaining weight, fatigue and failure to grow resulting in a wasting disease called ‘Kwashiorkor’ most common in third world countries where the body looks malnourished while the abdomen is swollen. * Cachexia can effect skeletal depletion and protein degradation which is mostly associated with aids and cancer sufferers.
Impaired immunity * Have serious effects on our bodies capability to fight disease. * Antibodies that defend disease are made up of proteins.
Blood and hormonal disorders * Inherited conditions such as protein C and S deficiency can cause swelling, redness, severe pain and blood clots due to a lack of protein hemoglobin to carry oxygen around the body. * Hormonal disorders can affect digestion, metabolism and blood sugar levels.
(livestrong, 2012)
-Carbohydrates can be split into three categories, sugar, starch and fiber. Sugar comes in the form of honey, syrups, candy bars and a lot of processed food and can provide us with short term energy boost as they are simple sugars and easily digested by the body giving us the quick energy boost but can have side effects such as a ‘sugar withdrawal’ causing us to feel more tired than before we had the quick fix. Starches come from foods such as potatoes, pasta and brown rice, these are more complex sugars and take longer for the body to digest providing us with a more sustained source of energy without the sugar withdrawal. Fibers are non-digestible forms of food which come from fruits, grains and vegetables although these do not provide us with an energy boost as the other two it is vital in providing us with a healthy intestinal system. It is recommended that 40-55% of our diet should contain a mixture of the three sources of carbohydrates to maintain a healthy body.
Carbohydrates are not created equally some are absorbed into the blood quicker than others. Too much of the same type of carbohydrates can increase the blood sugar level, the more refined and starchy carbohydrates or rapidly digested starch (RDS) are absorbed into the blood much quicker causing the blood sugar level to rise and tend to have a high Glycemic index (the measure of blood sugar levels) this then results in the amount of insulin in the blood. When levels of sugar are high the body will store the sugar as glycogen in the liver and muscles.
GI food index Low GI foods | GI index 55 or less | Medium GI foods 56-69 | GI index | High GI foods 70-100 | GI index | Low-fat yoghurt with sweetener | 14 | Muesli, non toasted | 56 | White bread | 70 | Cherries | 22 | Pitta bread | 57 | Bagel | 72 | Red lentils | 26 | Ice cream | 61 | French fries | 75 | Skimmed milk | 32 | Raisins | 64 | Jelly beans | 80 | Apple juice, unsweetened | 40 | Pineapple, fresh | 66 | Cornflakes | 84 | Orange juice | 46 | Mars bar | 68 | Baguette | 95 | Sweetcorn | 55 | Wholemeal bread | 69 | White rice, steamed | 98 |
(weightlossresources, 2012)
The GI index reflects the relative rate of elevation in blood sugar levels which in turn affects the amount of insulin in the blood. Sugar has a GI of 100 with the GI of white bread being 98, which means 98% sugar. Low fat yogurt has a low GI of 14% which means the rate of sugar is much lower. It is recommended to control the rate of insulin lower GI foods are much healthier and help control weight gain, hypoglycemia and type 2 diabetes.
A lot of carbohydrate deficiencies come about from low or no carbohydrate diets this can result in your body not creating enough energy which results in fatigue and weakness. A lack of carbohydrates in the diet will mean the body will not be able to create enough energy to fight off disease and the ability to heal wounds. Without the required amount of carbohydrates in the body the immune system will suffer without the essential vitamins and minerals received from carbohydrates. Hypoglycemia can be caused be low or high carbohydrate diets, this is when the blood sugar levels fall below 70mg/dL. This can be a result of not enough glucose being released into the body, glucose being released too slowly or too much insulin in the body which can result in diabetes. So it is essential that we maintain a well balanced carbohydrate diet (ncbi.nlm.nih, 2012).
-Lipids are found in food in the form of triglycerides which consist of fatty acids and glycerol, other types of dietary lipids are phospholipids and cholesterol which are not essential dietary requirements after the age of 2. The different types of fat can be broken down further as labeled in the table below
Table of dietary fats types, food sources and effects on blood lipid levels. | Type of Fat | Dietary Sources | Total Cholesterol | LDL-cholesterol | HDL-cholesterol | Triglycerides | Saturated Fat | Red meat, cheese, butter, commercially fried foods and baked goods | Increase | Increase | No effect | No effect | Trans Fats | Commercially fried foods and commercially prepared snacks and baked goods | Increase | Increase | Slight
Decrease | No effect | Monounsaturated Fats | Nuts, olives, avocados, olive & canola oils | Decrease | Decrease | No effect | No effect | Polyunsaturated Fats
: Omega-6 | Corn, soybean and safflower margarine & oils | Decrease | Decrease | Decrease | Unknown | Omega-3 | Salmon, mackerel, herring, flaxseed, walnuts, walnut oil, soybean and soybean oil | Decrease | Decrease | No effect | Decrease |
(nuinfo-proto4.northwestern, 2012) | |
Lipids are an important part of a balanced diet and like carbohydrates they need to be respected and taken in proportion. Too much lipids in our diet such as saturated fats can increase the likely hood of high blood pressure, obesity, heart problems and diabetes, in contradiction to that the likes of the monosaturated and polysaturated fats can decrease the risks of heart problems and blood pressure. The recommended daily allowance of for fats is around 10-20 grams or 2-4 teaspoons. Sources like red meat might be high in protein but can contribute to high levels of cholesterol, so it is recommended that it is not consumed more than 3-4 times a week (nuinfo-proto4.northwestern, 2012).
Omega 3 and omega 6 are essential fatty acids that the body can’t produce and are associated with brain development, blood pressure regulation and immune system function. They have many uses when it comes to health benefits in supporting some of the following conditions, asthma, skin disorders, diabetes, arthritis, osteoporosis, depressive disorders and digestive difficulties amongst many others (globalhealingcenter, 2012).
Some of the most common diseases associated with lipids are Gaughers disease and Tay-sach’s disease. Gaughers disease involves the storage of lipids. This is caused by a deficiency of an enzyme called glucocerebrosidase, the enzyme is unable to break down the fatty acids properly. Fat collects in the brain, liver, lungs, bone marrow, kidneys and spleen causing the organs to swell and malfunction along with bone disorders and lesions. Gaughers disease is inherited and most common within children and can be fatal within 1 year (livestrong, 2012).
Tay-sach’s disease is a lipid disorder in which a specific called ganglioside (GM2) accumulates in the brain, tissues and the nerve cells. This is a result of the body lacking the enzyme hexosaminidase which is responsible for breaking down the gangliosides. Tay-sach’s disease is most common in young children causing trouble swallowing, blindness and deafness it can also cause paralysis, muscle atrophy and seizures. There is still no cure for Tay-sach’s disease, all that can be done is the controlling of seizures and nourishment through a tube. Children suffering from Tay-sach’s disease are unlikely to live past 4 years old (livestrong, 2012).
-Water is a vital part of our dietary requirements with around 80% of our cells made up of water and 50-70% of our body mass the constant replenishment of water is needed for our survival. Water helps to regulate many functions in the body such as temperature control, the transportation of oxygen and nutrients, assisting in chemical reactions, the elimination of waste products through our urine, lubrication of joints, a major component of mucus and giving the shape and stability to our cells. We need to constantly consume water, the average amount required is 2-3 liters a day but this can vary from person to person depending on the levels of exercise being undertaken, the living environment ( high altitude or hot countries) or medical condition (about.com, 2012).
Water is not only available in the form of liquid, we can take in a lot of fluids from various foods such as fruit and vegetables which have a high concentration of water. Caffeine and alcohol can have different effects on the body, although they might be liquids and quench your thirst at the time they cause the body to pass water more quickly causing dehydration. Some of the symptoms of dehydration can be headaches, tiredness and loss of concentration (bbchealth, 2012).
No deficiency diseases are directly linked with water but the lack of water or dehydration can cause serious problems. Dehydration has a negative effect on our bodily functions, the constant drinking of fluids helps to flush out toxins that are harmful to our bodies and helps with the delivery of nutrients and oxygen. Constant dehydration can lead to such problems as kidney stones, chronic pain, arthritis, fatigue and in some cases even death.
-Minerals are described as inorganic compounds that help to support cell functions. Some of the more common minerals would be calcium, iron, potassium, zinc and magnesium. Listed below are some of the benefits and the RDI of minerals.
Table of benefits and RDI of minerals. Minerals | benefit | RDI for men 19-50 | RDI for women 19-50 | Calcium | Teeth, bone growth | 1g per day1.2g 50yrs + | 1g per day1.2g 50 yrs + | Iron | Cell formation, oxygen transfer, menstrual cycle | 8mg per day | 18mg per day | Potassium | Fluid balance | 4.7g per day | 4.7g per day | Magnesium | Bone growth | 410mg per day | 410mg per day | Zinc | Protein synthesis | 11mg per day | 8mg per day |
(livestrong, 2012)
Lack of iron in the blood can result in anemia, the red blood cells carry different gases between the lungs and body tissues, as the blood passes through the lungs the red blood cells then absorb oxygen which is carried by the hemoglobin molecules within the cell. The cell releases the oxygen into the tissues and collects the carbon dioxide. The blood returns to the lungs, relasing the carbon dioxide where it is then released by the body and the process starts over again. Iron is an essential part of this process as an insufficient supply of reduces the rate of hemoglobin made by the bone marrow causing red blood cell shortage and too much carbon dioxide left in the body causing iron deficiency anemia (livestrong, 2012).
Calcium deficiency which is also known as hypocalcaemia is when a person has insufficient levels of calcium in the blood. Various symptoms include muscle cramps, back spasms pins and needles in the mouth fingers and toes, bones can become porous and fragile, teeth start to decay and brittle nails. The lack of calcium and vitamin D are major causes, if the body has insufficient levels in the blood it removes it from high areas of concentration such as the bones and teeth transferring it to the organs. If poor calcium intake continues it will have a major effect on the body. This can also result from the lack of the parathyroid hormone (PTH) which helps increase the concentration of calcium into the blood stream.
-Vitamins are a vital nutrition for a health body and are found in many different foods and come from the two words ‘vital’ and ‘amins’. Vitamins can be split into two categories water soluble and fat soluble. The water soluble vitamins can be dissolved in water and excess amounts can be passed harmless through the urine. Fat soluble vitamins do not dissolve in water as easily and are stored in the body for longer. Some of the different types of vitamins are detailed in the table below along with the benefits and the RDI. Vitamins | Benefits | RDI for males 19-70 | RDI for females 19-70 | Fat or water soluble | Vitamin A | Skin, teeth and bone growth | 900mg | 700mg | Fat soluble | Vitamin C | Antioxidant | 90mg | 75mg | Water soluble | Vitamin E | Antioxidant, formation of red blood cells | 15mg | 15mg | Fat soluble | Vitamin K | Help blood coagulation | 120 micrograms | 90 micrograms | Fat soluble | B vitamins | Energy, metabolism | | | Water soluble | B1 thiamine | Energy, metabolism | 1.2mg | 1.1mg | Water soluble | B2 riboflavin | Energy, metabolism | 1.3mg | 1.1mg | Water soluble | B3 niacin | Energy, metabolism | 16mg | 14mg | Water soluble | B5 pantothenic acid | Energy, metabolism | 5mg | 5mg | Water soluble | B6 | Energy, metabolism | 1.3mg 19-501.7mg 51-71 | 1.3mg 19-501.5mg 51-70 | Water soluble | B7 biotin | | 30 micrograms | 30 micrograms | Water soluble | B9 folate | Energy, metabolism | 400 micrograms | 400 micrograms | Water soluble | B12 | Energy, metabolism | 2.4 micrograms | 2.4micrograms | Water soluble |
(Livestrong, 2012)
A healthy and balanced diet with all the required vitamins can keep many illnesses away from the common cold to xerosis. Sometimes the body has an inability to break down or absors certain vitamins and can cause major illnesses. Keratomalacia is a vitamin A deficiency that is caused by both dietary intake and for metabolic reason. Keratomalacia affects both eyes and can cause severe eye sight problems and blindness. Vitamin A is essential for our ability to see and for bone growth and without it our eye sight will deteriorate. Keratomalacia affects the eyes causing poor vision at night or in dim light (night blindness) followed by progressive cloudiness and softening of the corneas. If this is not treated dry foamy silver grey deposits or bitot spots will appear on membranes in the whites of the eye, this will continue to the coneal infection, rupture and the degeneration of the tissue resulting in blindness. Vitamin a deficiency mostly occurs during infancy and childhood Keratomalacia can occur as a secondary condition to diseases associated with impaired absorption, storage or transport of vitamin A such as ulcerative colitis, liver disease celiac disease and any other condition that might affect the absorption of fat-soluble vitamins (everydayhealth, 2012).
Rickets is caused by a deficiency of vitamin D, the disorder becomes apparent during infancy and childhood as it is needed most at this stage of growth and can be caused by poor nutrition, lack of exposure to the sun or the inability to absorb nutrients in the intestines. Vitamin D is a vital function in the metabolism of calcium and phosphorus in the body which affects how calcium is deposited into the bones and is essential for bone development. Some of the major symptoms of rickets includes bone diseases, slow growth and restlessness with deformity of the pelvis causing bow legs and pigeon chest and is most common in developing countries (web.md, 2012). Vitamin D deficiencies can affect people of all ages with middle aged people developing osteomalacia usually pregnant or breast feeding women due to the transferring of vitamins to the baby and the elderly developing osterporosis which can be treated by more exposure to the sun.
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Aim
The aim of this experiment is to identify different food groups within several different unknown solutions. This will be carried out by placing the unknown solutions into separate test tubes and using different chemical indicators to see if any reactions occur. Each food group will act different when the chemical indicator is added, some will change colour while others will separate.
Introduction
Food is a vital source of energy that is needed for survival, without this energy source our bodies wouldn’t be able to function. All food can be broken down into various food groups such as water, proteins, carbohydrates, vitamins, fats, fibre and minerals. Our bodies need all of these food groups to function with each of them playing a specific role. These food groups are present in our every day food and are taken into our body through a process of digestion. The food is chewed up and broken down into smaller bits in the mouth and then travels down to the stomach where it is broken down further by the hydrochloric acid in the stomach in a process called chemical digestion. Once the food has been broken down it is then absorbed by the blood to provide the various functions that our body needs to survive. We can get some of these food groups by other means such as vitamin injections, tablets …show more content…
or food supplements. These are generally taken when our bodies are not able to break down certain foods down, have allergies or vegetarians.
There are many different ways we can test food for the presence of certain substances within the food we eat. To test for carbohydrates or sugar in food a liquid called Benedict’s reagent is used, Benedict’s reagent contains sodium citrate, sodium carbonate and copper sulphate. Benedict’s reagent is mixed with a sample of food and then heated, if any reducing sugars such as glucose are present it will produce a precipitate. Depending on the amount of reducing sugar present the colour will change from yellow to brick red, the darker the precipitate goes the more concentration of sugar is in the food. This can be used to test for diabetes, by testing for sugar in the urine.
More complex sugars such as starch can be tested for by using iodine, starch has a helix configuration with enough dimensions to accommodate the iodine molecules which in turn interact with the glucose molecules in the starch. When starch is present the the liquid will turn a blue-black colour indication the presence of starch.
The test for proteins is known as the Biuret test, this uses a combination of sodium hydroxide and copper sulphate mixing them with the food will produce a colour change from blue, pink, lilac or violet depending on the concentration of proteins present.
Lipids are characterised by their insoluble nature in water so to test for the presence of lipids a organic solvent called ethanol (meths) is used. When the unknown solution and ethanol is mixed together and diluted with a small amount of water. The presence of lipids will give a white cloudy like emulsion.
To test for the presence of vitamin C a blue dye called DCPIP is used, the dye will lose its colour when in the presence of vitamin C (but not for other vitamins which are composed of different chemicals).
There are many reasons why we need to know the presence of different substances in food, foods high in sugar may be a vital source of energy but not taken in proportion can lead to health problems such as obesity and diabetes, excess amounts of lipids in food can lead to high cholesterol which may cause heart problems, proteins are important in our diet as they act as a catalyst for the chemical reactions that occur in our bodies, vitamin C helps maintain strong bones and good eyesight. To know what is in our food helps to moderate what we eat providing us with all the nutrition we need for a healthy body.
Materials and methods
Materials * Test tube rack * Test tubes * Beaker * Pipette * Boiled water * Filter paper * Benedict’s solution * Iodine * 2M sodium hydroxide * 1% copper sulphate * `Ethanol * Water * DCPIP solution 0.1% Methods
Method for Benedict’s test for reducing sugars. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknow solution added from the corresponding bottles using a pipette. * A measurement of 2 cm3 of Benedict’s solution was added to each of the test tubes using a pipette. * A beaker was filled with boiled water. * All the five test tubes were placed in the beaker with the boiled water for five minutes. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the iodine test for starch. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknow solution added from the corresponding bottles using a pipette. * A measurement of 4 drops of iodine solution was added to each of the test tubes. * The test tubes were left for 2 minutes. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the Biuret test for proteins. * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E from the corresponding unknown solution. * Each test tube had 2cm3 of unknown solution added from the corresponding bottles using a pipette. * A measurement of 2cm3 of 2M sodium hydroxide was added to each of the test tubes. * Each test tube was shaken gently to mix the solutions. * A measurement of four drops of 1% copper sulphate was slowly added to the test tubes one drop a time. * The test tubes were observed for two minutes and the results were recorded in a table.
Method for the emulsion and paper tests for lipids.
Emulsion test * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E. * A measurement of 2cm3 of ethanol (meths) was added to each of the test tubes. * A measurement of 2cm3 of the corresponding unknown solution was added to each of the test tubes. * The top of each of the test tubes were covered with Parafilm and gently shaken. * A measurement of 5 drops of water was added to each of the test tubes. * The top of each of the test tubes were covered with Parafilm and gently shaken. * The test tubes were observed for two minutes and the results were recorded in a table.
Paper test * A piece of filter paper was used. * The filter paper was divided into five sections. * Each section was labelled A-E to correspond with the unknown solution * A measurement of two drops of each of the unknown solutions was placed on the filter paper. * The filter paper was observed after five minutes and after ten minutes and the results were recorded in a table.
Method for the DCPIP test for vitamin C * A test tube rack was used containing empty 5 test tubes. * Each test tube was labelled with the letters A-E. * A measurement of 2cm3 of 0.1% DCPIP solution was added to each of the test tubes. * A measurement of 2cm3 of each of the unknown solutions was slowly added drop by drop to each of the corresponding test tubes. * The test tubes were observed for two minutes and the results were recorded in a table.
Table of results for Benedict’s solution test for reducing sugars. solution | Positive/Negative reaction for reducing sugar | Original colour | Colour change | A | Negative | Cloudy White translucent | Yes, turned light blue translucent | B | Positive | Clear, translucent | Yes, turned dark orange | C | positive | White, milky | Yes, turned yellow | D | Positive | Cloudy grey/black translucent | Yes, turned dark orange | E | Negative | Gold, rich oily | No | The test for reducing sugars provided two positive results, both unknown solutions A and D turned dark orange in colour confirming presence of vitamin A. Unknown solution C turned yellow in colour which indicated a very low presence of reducing sugar.
Table of results of iodine test for Starch. solution | Positive/Negative reaction for starch | Original colour | Colour change | A | Positive | Cloudy White translucent | Yes, turned charcoal-black | B | Negative | Clear, translucent | No | C | Negative | White, milky | No | D | Negative | Cloudy grey/black translucent | No | E | Negative | Gold, rich oily | No |
Unknown solution A tested positive for the presence of starch, with none of the other unknown solutions having any colour change reactions.
Table of results of Biuret test for proteins. solution | Positive/Negative results for proteins | Original colour | Colour change | A | Negative | Cloudy White translucent | Yes, slight blue tint | B | Negative | Clear, translucent | No | C | Positive | White, milky | Yes, turned purple | D | Negative | Cloudy grey/black translucent | Yes, turned bright yellow | E | Negative | Gold, rich oily | No |
Unknown solution C tested positive for the presence of proteins with two of the other solutions having a reaction but negative for the presence of proteins.
Table of results for emulsion test for Lipids. solution | Positive/Negative reaction for lipids | Original colour | Colour change | A | Negative | Cloudy White translucent | No | B | Negative | Clear, translucent | No | C | Negative | White, milky | No | D | Negative | Cloudy grey/black translucent | No | E | Positive | Gold, rich oily | Yes, turned milky white and cloudy |
Unknown solution E tested positive for the presence of the lipids, turning a cloudy milky white colour with none of the other solutions having any positive results or colour changes.
Table of results for DCPIP test for Vitamin C. solution | Positive/Negative reaction for vitamin C | Original colour | Colour change | A | Negative | White | No | B | Negative | Clear, translucent | No | C | Negative | White | No | D | Positive | Cloudy grey/black translucent | Yes, clear with a slight gold tint | E | Negative | gold | No |
Unknown solution D tested positive for the presence of vitamin C with none of the other unknown solutions having any positive reactions or colour changes
Summary
After the completion of the test all five unknown solutions were identified as labelled below.
Solution A - starch
Solution B – reducing sugar
Solution C – protein
Solution D – vitamin C
Solution E – Lipids
The test to identify a number of food groups in unknown solutions provided positive results with all the unknown solutions being clearly identified. The test for reducing sugars provided two positive results, both solutions B and D turned dark orange. This was the result of a vitamin C tablet being used in the unknown solution D which contains a small amount of reducing sugar. Some of unknown food groups reacted with the solutions changing the colour and appearance but did not provide positive results as the changes did not correspond with the specific colour needed to confirm the presence of the unknown foods.
Conclusion
After completion of the experiment all five unknown foods were identified correctly, the methods used provided positive results. The test for reducing sugars provided two results with the unknown foods B and D testing positive this was due to the unknown food in test tube D being a vitamin E tablet which contains a small amount of reducing sugar. Although the test provided positive results improvements could be made for future experiments. A more pure source of vitamin A should be used the next time this would eliminate any chance of having two positive results for the reducing sugars. More foods could of been used containing different amounts of protein this would of provided varied results showing the different colours from yellow to dark orange and the different concentrations each food contained.
The unknown food containing the lipids portrayed a specific trend, when mixed with the various solutions it formed a layer above the solution keeping the solution at the bottom. From the way the lipids behaved due to them being hydrophobic it was possible to hypothesize that the unknown food was the lipids before it was mixed with ethanol. The paper test for the lipids also provided positive results with the rest of the unknown foods drying into the paper while the lipids left a translucent mark.
Overall the experiment was very successful, if the experiment was to be repeated more unknown foods could be used of both solid and liquid forms. This would provide different forms of concentration when tested giving a more varied set of results. Foods could be used that contain more than one of the food groups and too try and identify what the food is.
The structure of proteins
Proteins are one of the most structural complex macromolecules in biochemistry and make up over 50% of the dry mass of a cell.
Each protein is made up of a linear chain of amino acids linked together by peptide bonds (all peptide bonds are covalent bonds). The amount of amino acids bonded together can vary from tens too thousands, creating different proteins. There are 20 different amino acids in living organisms and the combination of these amino acids linked together in different polypeptide chains can result in trillions of different combinations of chains creating many different proteins (proteincrystallography,
2012).
Amino acids can be split into two groups, the basic amino group (-NH2) and the acidic carboxyl group (-COOH) the combination of these creating amino acids, as the amino acids have both a base and a acid present it is said to be amphoteric. All amino acids contain carbon, oxygen, hydrogen and nitrogen with some containing sulphur as well. The two groups are linked to each other by the same carbon atom. The diagram below shows one of the simpler amino acids glycine.
-NH2 and -COOH groups linked by a carbon atom. (winona, 2012)
The rest of the amino acid is made up by a side chain represented by the H in the diagram above. Whilst all amino acids have the same basic structure, they all differ in character. The difference comes from the side chains in the groups. Some have extra carboxyl groups while others have extra amino groups and the structure and layout being different for each amino acid polypeptide chain (advanced biology, 2012).
Amino acids are monomers of protein, monomers are molecules that can join together to form larger chains known as polymers (thefreedictionary, 2012). In proteins the amino acids are joined together by bonds called ‘peptide bonds’. The peptide bonds are formed when the amino group of one of the amino acids reacts with the acidic carboxyl group of another neighbouring amino acid linking them together, creating the peptide bond (-CONH). An example of a dipeptide bond forming is detailed in the diagram below. When the carboxyl group from one amino acid glycine bonds with an amino group from a alanine amino acid creating the bond. The bond can be completely different if the opposite groups are used from the amino acids.
Two different formations of amino acids bonding
Alanyl-glycine glycine-alanyl (Chemspider, 2012) When the two amino acids join together it causes a loss of water (H2O) known as a condensation reaction (advanced biology, 2012). Polypeptide chains will be formed by amino acid residue (during to the formation of the chains, water is lost so the peptide chains are made up from the remaining biochemical’s or the ‘the amino acid residue’). The joining of two amino acids is known as a dipeptide chain, three amino acids is known as a tripeptide chain while any more is known as a polypeptide chain. Once the polypeptide chain has reached 50 plus amino acids it is then regarded as a protein.
The peptide bonds formed and the polypeptide chain (Molecularsciences, 2012)
The structure of a protein can be split into four different groups, the primary structure, secondary structure, tertiary structure and quaternary structure. The four different groups of the structure of a protein show how the amino acids form from their original peptide bonds to evolve into large complex molecular structures. The amino acids form these complex three dimensional structures is all controlled from the very start by the coded DNA in the nucleus. Proteins relay heavily on the shape that is created within the coding of these three dimensional structures, the majority of proteins are enzymes which help catalyse biochemical reactions in the body. Without the specific shapes of the active site of an enzyme it would not be able to react with the substrate molecules (protein structure, 2012).
Lock and key model
-The primary structure of a protein relates to the number of amino acids and the sequence they are held together by the Amino acids that link together to form the polypeptide chains peptide bonds in the polypeptide chains, this is controlled by the DNA coding within the chromosomes in the nucleus. If one amino acid is altered during the formation of the sequence it can alter the properties of the protein completely.
(Neb, 2012) The alpha helix and the beta sheet -The secondary structure of a protein involves the polypeptide chain starting to take shape or folding up, this is the result of the hydrogen bonding which plays an important role in stabilizing the folding patterns. There are two very distinct formations of the secondary structure. The alpha (α) helix and the beta (β) pleated sheet. The alphas helix is a coiled or spiral in shape while the beta is flat like a sheet of paper. The hydrogen bonds keep the structures in shape. Most proteins will have a combination of both of these structures.
(Samford, 2012) Tertiary structure of alpha helix and beta sheets The tertiary structure starts to develop its complex three dimensional globular structure, the atoms are arranged within a single polypeptide chain unique to that protein. The tertiary structure comes about when the molecules are further folded and are held together in there complex shape by a combination of four different types of bonds. Hydrogen bonds which are relatively weak but help to stabilize the protein molecules, ionic bonds which relay on electrostatic interaction between the oppositely charged ions, disulphide bonds are formed between two cysteine amino acids that are found together, a strong double bond (ccbcmd.edu, 2012) will form between the sulphur atoms within the cysteine monomers (S=S) and Van Der Waals bonds. Some proteins are complete at this stage.
Where two Cysteine amino acids are found together, a strong double bond (S=S) is formed between the Sulphur atoms within the Cysteine monomers.
Bonds formed in a quandary structure The quandary structure
The quaternary structure is composed of multiply subunits of polypeptide chains linked together forming a complex molecule. The polypeptide chains are mainly held together by a form of hydrophobic interactions. When the polypeptide chains fold into a three dimensional shape it exposes its polar sides to an aqueous environment and shielding its non-polar side chains. Some hydrophobic sections are still left exposed, these sections will then link up with exposed chains from other polypeptide chains creating the quandary structure, and a mixture of non-covalent bonds will also hold the complex shape in place (alevelnotes, 2012) An example of a quandary structure diagram of a hemoglobin protein is a hemoglobin protein which has four polypeptide chains linked together, two alpha (α) polypeptide chains and two beta (β) polypeptide chains around an inorganic prosthetic haem group. The purpose of the hemoglobin protein is to carry oxygen around in the blood, with the use of the haem group which contains positive iron ions (Fe2+) which binds to the oxygen.
(myweb, 2012)
Proteins can be classified in many different ways and can be split into different groups, each group of protein provides a different and vital role in our body with some of the proteins sharing similar properties.
Enzymes
* Catalyze chemical and biochemical reactions * Contains the biggest group of proteins * Responsible for all metabolic reactions in our cells * Involved in DNA and RNA * Hexokinase is a protein enzyme
Hormones
* Responsible for regulation of processes in organisms * Are small in size * Insulin is a protein hormone
Transport hormones * Transportation of ions and chemical compounds in the body * Insulin is a protein hormone * Haemoglobin is a transport hormone
Immunoglobulin or antibodies * Neutralize foreign molecules in the body such as infection * Antibodies can act as enzymes * Fibrin is a immunoglobulin protein
Structural proteins * Maintain structures of other biological components * Formation of the the organisms of the body * Collagen is a structural protein
Motor proteins * Convert chemical energy into mechanical energy * Responsible for muscular motion * Actin is a motor protein
Receptors
* Responsible for signal detection and translation * Rhodopsin is a receptor protein
Signaling proteins * Involved in the signaling translation process * Have properties of enzymes * GTPases is a signaling protein
Storage proteins * Contain energy released during metabolism processes * Ovalbumin is a storage protein
(Proteincrystallography, 2012)
| |
The structure of carbohydrates
Carbohydrates also known as carbs are an important part of our daily diet, they provide a vital energy source for the body. A certain amount of carbs is needed for the body to function properly and without this in our daily diet we can suffer from problems such as muscle cramps, fatigue and poor mental functions. Carbohydrates can be broke down into two groups simple carbohydrates, or monosaccharide’s and Classification of different forms of sugars complex carbohydrates, or polysaccharides. Simple carbohydrates are more easily digested by the body giving a brief energy boost and are found in a lot of processed foods, candy bars, white rice and white bread. Complex carbohydrates take a lot longer for the body digest this also results in a more sustained level of energy for the body compared to simple carbs, foods such as brown bread, brown rice, oatmeal, potatoes and pasta contain complex carbohydrates (wisegeek, 2012).
Carbohydrates are the biggest group of organic compounds found in all living things. (fao, 2012) All carbohydrates can be broke down into three elements, hydrogen, oxygen and nitrogen with the ratio of 2:1 between hydrogen and oxygen the same as in water and can be represented by the general formula Cx(H2O)y . Simple carbohydrates or monosaccharide’s are made up of single sugar units and sweet tasting such as glyceraldehydes, glucose, ribose, fructose, mannose and galactose. These are the building blocks or monomers Isomer of glucose of the more complex carbohydrates. The best known of these would be glucose which has the chemical symbol C6H12O6 or also known as a hexose sugar as it contains six carbon atoms. Almost all naturally occurring sugars found in carbohydrates are isomers as each individual sugar can have different arrangements of the same chemical formula.
Disaccharides form when two monosaccharide’s bond together by a glycosidic bond. The glycosidic bonds are covalent bonds between the adjoining –OH groups of the sugar, when the bond forms between the two molecules it produce a loss of water called a condensation reaction. The covalent bond between the two molecules allows the body to break down the bonds easily creating energy. When glucose and glucose are bonded together it results in the formation of maltose. Some other combinations of disaccharide bonds are glucose + fructose which make sucrose and glucose + galactose which make Lactose.
Complex carbohydrates or Polysaccharides are formed by the joining of many monosaccharides linked together a glycosidic bond. A glycosidic bond is a type of covalent bond the joins two monosaccharides together, this takes place between the terminal end and the reducing ends of the sugar (the reducing end being towards the carbon atom in the molecule and the terminal being at the opposite end). This linkage produces a dehydration reaction where a molecule of water is released, the condensation is known as the Fisher glycosidation. This process can be reversed by a process of hydrolysis in which water is added to break the sugar down (Swarthmore, 2012). The more complex the sugar the harder it is to break down, thus being the reason why simple sugars give quick energy bursts while the more complex polysaccharide chains give longer lasing energy. if any excess sugar remains in the blood after it is broken down it is removed by the pancreas by the hormone insulin and stored in the liver and muscles as glycogen, this can then be broken down again into glucose when required by the body. Starch is a form of a complex sugar which is used by plants to store energy and when eaten by animals is then turned into glycogen.
The structure of lipids
The biochemical group for lipids includes fats, waxes and oils and contains the elements carbon, hydrogen and oxygen similar to carbohydrates but containing less oxygen. Lipids are hydrophobic molecules and can only be dissolved hydrocarbon tail of a triglyceride in organic solvents such as ethanol, propanone and ether. Unlike proteins and carbohydrates the monomers for lipids are made up of two different base units, fatty acids (monocarboxylic acids) and an alcohol called glycerol in a covalent bond called a ester bond in the ratio of 3:1 making triglyceride by a dehydration synthesis. (Proprofs, 2012
Lipids have hydrophobic properties due to the hydrocarbon tails containing somewhere between 14 and 22 carbon atoms surrounded by hydrogen atoms and are generally described as fatty acids as the –COOH group tends to slightly ionise to produce hydrogen ions which is the same property as acids. Fats and oils are both formed this way with one of the differences being oils are liquid while fats are solid at room temperature (advanced biology, 2012).
Fats and oils can be described as saturated and unsaturated depending on how they are bonded together. Fats (saturated) have all single bonds between the carbon and hydrogen atoms in the tail, this means that the carbon atoms can bond to the maximum amount of hydrogen atoms possible. The hydrocarbon tails are straight and the atoms can pack closely together making saturated fats solid at room temperature. (nature, 2012)
Oils (unsaturated) unlike fats have some double bonds in the tails causing kinks in the shape of the molecule, due to these double bonds between the carbons they can’t bond with as many of the hydrogen molecules, this in turn means the unsaturated fat cant pack as closely together making them an oil at room temperature, oils with more than one double bond are called polyunsaturated (Biology.clc.uc, 2012).
Lipids like carbohydrates and proteins can be split into different categories, with each category providing different functions within the body. All lipids share similar characteristics such as they are insoluble in water and a provide a high source of energy, the energy is harder to be released into the body due to insoluble nature so they are not a readily available energy source.
Phospholipids differ from triglyceride in they have two fatty acid chains and a phosphate group linked to a glycerol group. Phospholipids are mainly found in the membranes of cells due to them having both hydrophobic and hydrophilic properties. The phospholipids have the hydrophilic properties due to the phosphate group which is ionised making it negatively charged and attract water molecules. Phospholipids having both these properties help them regulate what molecules come in and out of a cell.
Glycolipids are molecules that contain single sugar units such as galactose or glucose. Glycolipids can range from having one sugar unit or more complex containing up to seven sugar molecules. Glycolipids can be found in the nerve cells and are used as a marker for cellular recognition and provide energy for cells.
Cholesterol consists of four hydrogen rings attached to a hydroxyl-hydrogen bond to oxygen group, cholesterol is also known as a steroid with the hydroxyl group providing it with amphipathic properties of being a hydrophobic and hydrophilic. Cholesterol is found in the blood and is not soluble. Due to cholesterol not being soluble it is carried to the cells via the help of lipoproteins. Too much cholesterol can be dangerous for the body but plays a vital role in in the cell membrane and works in conjunction with steroids.
Waxes are esters that are formed from more complex alcohols than glycerol along with fatty acids. Some of the uses of waxes occur mostly in plants but do occur in some animals providing a waterproof and protecting coating due to the hydrophobic properties (livestrong, 2012).
Human dietary requirements
To maintain a healthy body we must have a balanced diet, too little or too much of certain types of foods can have an adverse affect on the body causing defects, malnutrition or even death. To achieve a balanced diet we must take in all the required amounts of nutrition in a proportioned amount. We receive our nutrition from digesting food, the food is then broken down by the body to molecules small enough to be absorbed by the blood and then transported to where it is needed in the body. Nutrition provides energy to maintain the functions of the body such as strong bones, good eyesight, healthy skin, healthy organs and the ability of the body to repair itself. Some of the main dietary requirements needed by the body are proteins, carbohydrates, lipids, water, minerals and vitamins.
-Proteins are an important part of our daily diet, as all the cells in the human body contain protein and it makes up about 16% of our total body weight a daily intake is essential. When protein is digested into the body it is broken down into the different amino acids and absorbed into the blood and is part of some of the important chemicals within the body such as enzymes, hormones, neurotransmitters and DNA. The recommended daily intake (RDI) of protein can vary due to age or gender and whether you’re fit or pregnant. The RDI of protein is labelled below in the table and is worked out by multiplying the body weight of a person in kg by 0.8.
RDI of protein Weight in kilograms | Protein per day if you're not very active
(kg multiplied by 0.8) | Protein per day if you're active or pregnant
(kg multiplied by 1.3) | Protein per day if you're extremely active or in training
(kg multiplied by 1.8) | 45.5 kg | 36.4 g | 59.2 g | 81.9 g | 47.7 kg | 38.2 g | 62 g | 85.9 g | 50 kg | 40 g | 65 g | 90 g | 52.3 kg | 41.8 g | 68 g | 94.1 g | 54.5 kg | 43.6 g | 70.9 g | 98.1 g | 56.8 kg | 45.4 g | 73.8 g | 102.2 g | 59.1 kg | 47.3 g | 76.8 g | 106.4 g | 61.4 kg | 49.1 g | 79.8 g | 110.5 g | 63.6 kg | 50.9 g | 82.7 g | 114.5 g | 65.9 kg | 52.7 g | 85.7 g | 118.6 g | 68.2 kg | 54.7 g | 88.7 g | 122.8 g | 70.5 kg | 56.4 g | 91.7 g | 126.9 g | 72.7 kg | 58.2 g | 94.5 g | 130.8 g | 75 kg | 60 g | 97.5 g | 135 g |
(Fitsugar,2012)
A daily intake of protein is essential for the growth of hair, muscle, skin and connective tissue in our bodies and although our bodies are good at recycling protein we still need a constant supply to maintain a healthy life style. Some of the foods that are essential in maintaining this balanced diet are meat, eggs and dairy products which contain all the 20 amino acids available. Protein deficiencies tend to be rare if the right foods are ate, even with vegetarians and vegans such foods as soya milk, oatmeal, lima beans and spinach can be high sources of protein with all the amino acids required (lowcarbdiets.about, 2012).
An insufficient diet of protein can have some serious negative effects on the body.
Hair and skin * Hair will become brittle leading to alopecia or hair loss. * Wounds will take longer to heal. * Skin will undergo changes in pigmentation leading to dermatitis or pressure ulcers.
Muscles and growth * Muscle wasting and weakness resulting in a loss of muscle mass leading to protein deficiency disease called ‘marasmus’. * Insufficient protein in babies/children can led to problems in gaining weight, fatigue and failure to grow resulting in a wasting disease called ‘Kwashiorkor’ most common in third world countries where the body looks malnourished while the abdomen is swollen. * Cachexia can effect skeletal depletion and protein degradation which is mostly associated with aids and cancer sufferers.
Impaired immunity * Have serious effects on our bodies capability to fight disease. * Antibodies that defend disease are made up of proteins.
Blood and hormonal disorders * Inherited conditions such as protein C and S deficiency can cause swelling, redness, severe pain and blood clots due to a lack of protein hemoglobin to carry oxygen around the body. * Hormonal disorders can affect digestion, metabolism and blood sugar levels.
(livestrong, 2012)
-Carbohydrates can be split into three categories, sugar, starch and fiber. Sugar comes in the form of honey, syrups, candy bars and a lot of processed food and can provide us with short term energy boost as they are simple sugars and easily digested by the body giving us the quick energy boost but can have side effects such as a ‘sugar withdrawal’ causing us to feel more tired than before we had the quick fix. Starches come from foods such as potatoes, pasta and brown rice, these are more complex sugars and take longer for the body to digest providing us with a more sustained source of energy without the sugar withdrawal. Fibers are non-digestible forms of food which come from fruits, grains and vegetables although these do not provide us with an energy boost as the other two it is vital in providing us with a healthy intestinal system. It is recommended that 40-55% of our diet should contain a mixture of the three sources of carbohydrates to maintain a healthy body.
Carbohydrates are not created equally some are absorbed into the blood quicker than others. Too much of the same type of carbohydrates can increase the blood sugar level, the more refined and starchy carbohydrates or rapidly digested starch (RDS) are absorbed into the blood much quicker causing the blood sugar level to rise and tend to have a high Glycemic index (the measure of blood sugar levels) this then results in the amount of insulin in the blood. When levels of sugar are high the body will store the sugar as glycogen in the liver and muscles.
GI food index Low GI foods | GI index 55 or less | Medium GI foods 56-69 | GI index | High GI foods 70-100 | GI index | Low-fat yoghurt with sweetener | 14 | Muesli, non toasted | 56 | White bread | 70 | Cherries | 22 | Pitta bread | 57 | Bagel | 72 | Red lentils | 26 | Ice cream | 61 | French fries | 75 | Skimmed milk | 32 | Raisins | 64 | Jelly beans | 80 | Apple juice, unsweetened | 40 | Pineapple, fresh | 66 | Cornflakes | 84 | Orange juice | 46 | Mars bar | 68 | Baguette | 95 | Sweetcorn | 55 | Wholemeal bread | 69 | White rice, steamed | 98 |
(weightlossresources, 2012)
The GI index reflects the relative rate of elevation in blood sugar levels which in turn affects the amount of insulin in the blood. Sugar has a GI of 100 with the GI of white bread being 98, which means 98% sugar. Low fat yogurt has a low GI of 14% which means the rate of sugar is much lower. It is recommended to control the rate of insulin lower GI foods are much healthier and help control weight gain, hypoglycemia and type 2 diabetes.
A lot of carbohydrate deficiencies come about from low or no carbohydrate diets this can result in your body not creating enough energy which results in fatigue and weakness. A lack of carbohydrates in the diet will mean the body will not be able to create enough energy to fight off disease and the ability to heal wounds. Without the required amount of carbohydrates in the body the immune system will suffer without the essential vitamins and minerals received from carbohydrates. Hypoglycemia can be caused be low or high carbohydrate diets, this is when the blood sugar levels fall below 70mg/dL. This can be a result of not enough glucose being released into the body, glucose being released too slowly or too much insulin in the body which can result in diabetes. So it is essential that we maintain a well balanced carbohydrate diet (ncbi.nlm.nih, 2012).
-Lipids are found in food in the form of triglycerides which consist of fatty acids and glycerol, other types of dietary lipids are phospholipids and cholesterol which are not essential dietary requirements after the age of 2. The different types of fat can be broken down further as labeled in the table below
Table of dietary fats types, food sources and effects on blood lipid levels. | Type of Fat | Dietary Sources | Total Cholesterol | LDL-cholesterol | HDL-cholesterol | Triglycerides | Saturated Fat | Red meat, cheese, butter, commercially fried foods and baked goods | Increase | Increase | No effect | No effect | Trans Fats | Commercially fried foods and commercially prepared snacks and baked goods | Increase | Increase | Slight
Decrease | No effect | Monounsaturated Fats | Nuts, olives, avocados, olive & canola oils | Decrease | Decrease | No effect | No effect | Polyunsaturated Fats
: Omega-6 | Corn, soybean and safflower margarine & oils | Decrease | Decrease | Decrease | Unknown | Omega-3 | Salmon, mackerel, herring, flaxseed, walnuts, walnut oil, soybean and soybean oil | Decrease | Decrease | No effect | Decrease |
(nuinfo-proto4.northwestern, 2012) | |
Lipids are an important part of a balanced diet and like carbohydrates they need to be respected and taken in proportion. Too much lipids in our diet such as saturated fats can increase the likely hood of high blood pressure, obesity, heart problems and diabetes, in contradiction to that the likes of the monosaturated and polysaturated fats can decrease the risks of heart problems and blood pressure. The recommended daily allowance of for fats is around 10-20 grams or 2-4 teaspoons. Sources like red meat might be high in protein but can contribute to high levels of cholesterol, so it is recommended that it is not consumed more than 3-4 times a week (nuinfo-proto4.northwestern, 2012).
Omega 3 and omega 6 are essential fatty acids that the body can’t produce and are associated with brain development, blood pressure regulation and immune system function. They have many uses when it comes to health benefits in supporting some of the following conditions, asthma, skin disorders, diabetes, arthritis, osteoporosis, depressive disorders and digestive difficulties amongst many others (globalhealingcenter, 2012).
Some of the most common diseases associated with lipids are Gaughers disease and Tay-sach’s disease. Gaughers disease involves the storage of lipids. This is caused by a deficiency of an enzyme called glucocerebrosidase, the enzyme is unable to break down the fatty acids properly. Fat collects in the brain, liver, lungs, bone marrow, kidneys and spleen causing the organs to swell and malfunction along with bone disorders and lesions. Gaughers disease is inherited and most common within children and can be fatal within 1 year (livestrong, 2012).
Tay-sach’s disease is a lipid disorder in which a specific called ganglioside (GM2) accumulates in the brain, tissues and the nerve cells. This is a result of the body lacking the enzyme hexosaminidase which is responsible for breaking down the gangliosides. Tay-sach’s disease is most common in young children causing trouble swallowing, blindness and deafness it can also cause paralysis, muscle atrophy and seizures. There is still no cure for Tay-sach’s disease, all that can be done is the controlling of seizures and nourishment through a tube. Children suffering from Tay-sach’s disease are unlikely to live past 4 years old (livestrong, 2012).
-Water is a vital part of our dietary requirements with around 80% of our cells made up of water and 50-70% of our body mass the constant replenishment of water is needed for our survival. Water helps to regulate many functions in the body such as temperature control, the transportation of oxygen and nutrients, assisting in chemical reactions, the elimination of waste products through our urine, lubrication of joints, a major component of mucus and giving the shape and stability to our cells. We need to constantly consume water, the average amount required is 2-3 liters a day but this can vary from person to person depending on the levels of exercise being undertaken, the living environment ( high altitude or hot countries) or medical condition (about.com, 2012).
Water is not only available in the form of liquid, we can take in a lot of fluids from various foods such as fruit and vegetables which have a high concentration of water. Caffeine and alcohol can have different effects on the body, although they might be liquids and quench your thirst at the time they cause the body to pass water more quickly causing dehydration. Some of the symptoms of dehydration can be headaches, tiredness and loss of concentration (bbchealth, 2012).
No deficiency diseases are directly linked with water but the lack of water or dehydration can cause serious problems. Dehydration has a negative effect on our bodily functions, the constant drinking of fluids helps to flush out toxins that are harmful to our bodies and helps with the delivery of nutrients and oxygen. Constant dehydration can lead to such problems as kidney stones, chronic pain, arthritis, fatigue and in some cases even death.
-Minerals are described as inorganic compounds that help to support cell functions. Some of the more common minerals would be calcium, iron, potassium, zinc and magnesium. Listed below are some of the benefits and the RDI of minerals.
Table of benefits and RDI of minerals. Minerals | benefit | RDI for men 19-50 | RDI for women 19-50 | Calcium | Teeth, bone growth | 1g per day1.2g 50yrs + | 1g per day1.2g 50 yrs + | Iron | Cell formation, oxygen transfer, menstrual cycle | 8mg per day | 18mg per day | Potassium | Fluid balance | 4.7g per day | 4.7g per day | Magnesium | Bone growth | 410mg per day | 410mg per day | Zinc | Protein synthesis | 11mg per day | 8mg per day |
(livestrong, 2012)
Lack of iron in the blood can result in anemia, the red blood cells carry different gases between the lungs and body tissues, as the blood passes through the lungs the red blood cells then absorb oxygen which is carried by the hemoglobin molecules within the cell. The cell releases the oxygen into the tissues and collects the carbon dioxide. The blood returns to the lungs, relasing the carbon dioxide where it is then released by the body and the process starts over again. Iron is an essential part of this process as an insufficient supply of reduces the rate of hemoglobin made by the bone marrow causing red blood cell shortage and too much carbon dioxide left in the body causing iron deficiency anemia (livestrong, 2012).
Calcium deficiency which is also known as hypocalcaemia is when a person has insufficient levels of calcium in the blood. Various symptoms include muscle cramps, back spasms pins and needles in the mouth fingers and toes, bones can become porous and fragile, teeth start to decay and brittle nails. The lack of calcium and vitamin D are major causes, if the body has insufficient levels in the blood it removes it from high areas of concentration such as the bones and teeth transferring it to the organs. If poor calcium intake continues it will have a major effect on the body. This can also result from the lack of the parathyroid hormone (PTH) which helps increase the concentration of calcium into the blood stream.
-Vitamins are a vital nutrition for a health body and are found in many different foods and come from the two words ‘vital’ and ‘amins’. Vitamins can be split into two categories water soluble and fat soluble. The water soluble vitamins can be dissolved in water and excess amounts can be passed harmless through the urine. Fat soluble vitamins do not dissolve in water as easily and are stored in the body for longer. Some of the different types of vitamins are detailed in the table below along with the benefits and the RDI. Vitamins | Benefits | RDI for males 19-70 | RDI for females 19-70 | Fat or water soluble | Vitamin A | Skin, teeth and bone growth | 900mg | 700mg | Fat soluble | Vitamin C | Antioxidant | 90mg | 75mg | Water soluble | Vitamin E | Antioxidant, formation of red blood cells | 15mg | 15mg | Fat soluble | Vitamin K | Help blood coagulation | 120 micrograms | 90 micrograms | Fat soluble | B vitamins | Energy, metabolism | | | Water soluble | B1 thiamine | Energy, metabolism | 1.2mg | 1.1mg | Water soluble | B2 riboflavin | Energy, metabolism | 1.3mg | 1.1mg | Water soluble | B3 niacin | Energy, metabolism | 16mg | 14mg | Water soluble | B5 pantothenic acid | Energy, metabolism | 5mg | 5mg | Water soluble | B6 | Energy, metabolism | 1.3mg 19-501.7mg 51-71 | 1.3mg 19-501.5mg 51-70 | Water soluble | B7 biotin | | 30 micrograms | 30 micrograms | Water soluble | B9 folate | Energy, metabolism | 400 micrograms | 400 micrograms | Water soluble | B12 | Energy, metabolism | 2.4 micrograms | 2.4micrograms | Water soluble |
(Livestrong, 2012)
A healthy and balanced diet with all the required vitamins can keep many illnesses away from the common cold to xerosis. Sometimes the body has an inability to break down or absors certain vitamins and can cause major illnesses. Keratomalacia is a vitamin A deficiency that is caused by both dietary intake and for metabolic reason. Keratomalacia affects both eyes and can cause severe eye sight problems and blindness. Vitamin A is essential for our ability to see and for bone growth and without it our eye sight will deteriorate. Keratomalacia affects the eyes causing poor vision at night or in dim light (night blindness) followed by progressive cloudiness and softening of the corneas. If this is not treated dry foamy silver grey deposits or bitot spots will appear on membranes in the whites of the eye, this will continue to the coneal infection, rupture and the degeneration of the tissue resulting in blindness. Vitamin a deficiency mostly occurs during infancy and childhood Keratomalacia can occur as a secondary condition to diseases associated with impaired absorption, storage or transport of vitamin A such as ulcerative colitis, liver disease celiac disease and any other condition that might affect the absorption of fat-soluble vitamins (everydayhealth, 2012).
Rickets is caused by a deficiency of vitamin D, the disorder becomes apparent during infancy and childhood as it is needed most at this stage of growth and can be caused by poor nutrition, lack of exposure to the sun or the inability to absorb nutrients in the intestines. Vitamin D is a vital function in the metabolism of calcium and phosphorus in the body which affects how calcium is deposited into the bones and is essential for bone development. Some of the major symptoms of rickets includes bone diseases, slow growth and restlessness with deformity of the pelvis causing bow legs and pigeon chest and is most common in developing countries (web.md, 2012). Vitamin D deficiencies can affect people of all ages with middle aged people developing osteomalacia usually pregnant or breast feeding women due to the transferring of vitamins to the baby and the elderly developing osterporosis which can be treated by more exposure to the sun.
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