Endocrine System Review Sheet
Biology exam
Endocrine system:
Hormones: chemical messengers that coordinate the body’s activates. Substances secreted by cells that act to regulate the activity of other cells in the body. They are part of the endocrine system and they are slow acting but have a longer affect than neurotransmitters.
Functions:
* regulate growth, development, behavior, and reproduction. * Maintain homeostasis * Regulate metabolism and water and mineral balance * Respond to external stimuli * Exocrine glands: secrete substances ( water/enzymes/ mucus) through tube like ducts. * The ducts transport the substances to specific locations inside and outside the body.
Ex. Liver, sweat glands, mucus glands, salivary glands, other digestive glands
The endocrine system consists of:
* Endocrine glands: ductless organs …show more content…
that secret and make hormones either in the bloodstream or into extra cellular fluid
* Another hormones source: specialized cells in: brain, stomach, liver, small intestines, heart, and others.
__
Target cells: specific cells to which a hormone travels to produce a specific effect.
^ have receptors: proteins that bind specific signal molecules that cause the cell to respond.
(Found in: cell membrane/ cytoplasm/ nucleus of the cell)
How they work? 1. Each receptor binds to a specific hormone. 2. a hormone binds to a receptor 3. the binding triggers events that lead to changes within the cell.
__
second messenger is a molecule that initiates changes inside a cell in response to the binding of a specific substance to a receptor on the outside of a cell.
Urinary system:
Functions:
1. Maintains homeostasis by regulating the content of water and other substances in blood. 2. Removes waste.
Excretion: the process of removing metabolic waste.
Main waste products the need to be eliminated: * Carbon dioxide(from cellular respiration) removed by lungs * Nitrogenous compounds (from the breakdown of proteins) removed by kidneys
Ex. Urea: nitrogenous compound made by the liver.
Formation of urea: 1. Ammonia (nitrogenous waste) very toxic. Cell harming. Is in blood. 2. Blood is filtered from ammonia in the liver 3. Liver converts ammonia into urea 4. Urea enters blood stream then finds its way to kidneys 5. Urea is removed by kidneys
Organs in this system: 1. Kidneys:
Shape: bean shaped the size of a fist
Location: one behind the liver, one behind the stomach
Function: regulate the chemical composition of the blood
Structure:
- renal cortex (outermost portion of the kidney) 1/3 of kidney mass
- renal medulla (inner 2/3s of the kidney) consists of structures that carry urine, which empties into:
-renal pelvis (funnel shaped structure in the center of the kidney)
__
Blood flow: * Blood enters from: renal artery (transports waste and nutrients)
These nutrients are used by the kidney cells to carry out their life process.
Ex. Of a process: removal of waste. * Blood leaves from: renal vein: transports the filtered blood back to the heart.
__
NEPHRONS: the functional part of the kidneys
Shape: tiny tubes
Location: the kidneys
Function: making urine
Urine: amber colored liquid, its substances removed by the kidneys from the blood (water, toxins, urea, salt, and minerals: those remain in distal convoluted tubules)
All urine from all DCT goes to collecting duct. Osmosis occurs, 99% of water returns to blood.
Structure of nephron: * Bowman’s capsule: at an end of a nephron, cup shaped capsule surrounding a tight ball of capillaries that retains cells and large molecules in the blood and passes wastes dissolved in water through the nephron. * -------------------------------------------------
Glomerulus: a fine network of capillaries within the Bowman capsule. The capillaries come from arterioles.
THREE MAIN PROCESSES IN NEPHRONS: 1. Filtration: Materials from the blood are forced out of the glomerulus and into the Bowman’s capsule. 2. Reabsorption:
Water: goes back by osmosis (75% of it)
Minerals (sodium, calcium, potassium) / glucose: return by active transport 3. Secretion: substances pass from the blood into the filtrate.
__
Elimination of urine:
-------------------------------------------------
Collecting duct > renal pelvis> ureter> urinary bladder> urethra.
Excretory organs:
Lungs: detoxification, altering harmful substances so that they are not poisonous.
Skin: excretes water, salts, small amounts of nitrogen wastes, and other substances in sweat.
__
------------------------------------------------- excretion : correctly refers to the process during which substances must pass through a membrane to leave the body.
Digestive system: Is made up of: The digestive system is made up of the gastrointestinal tract, salivary glands, the liver, gallbladder, and pancreas.
Digestion: process of breaking down food into molecules the body can use.
Occurs in: * Gastrointestinal tract or Digestion tract: long, winding tube which begins at the mouth and winds through the body to the anus. * Organs in this tract carry out digestion
With aid of secretion from ducts that are not part of this tract.
The process: 1. Mechanical and chemical breakdown of food 2. Absorption of nutrients 3. Elimination of waste
I. Mouth: * incisors cut the food * molars grind the food the tongue keeps the food between the chewingness and moves it around against the roof of the mouth *hard palate* which is bony and hard. * Salivary amylase begins the chemical digestion of carbohydrates by breaking down some starch into the disaccharide maltose.
So food gets chewed, moistened and rolled into a bolus here.
Salivary glands: * Produce: saliva .. a mixture of water, mucus, and a digestive enzyme called salivary amylase. * Location: tiny glands in the lining of the mouth and three other larger glands.
II. Pharynx : open area that begins at the back of the mouth, serves as a passageway for both air and food. * Epiglottis: a flap of tissue, prevents food from entering the trachea, or windpipe, during swallowing. III. Esophagus: connects the pharynx with the stomach.
Structure: muscular tube approximately 25 cm long consists of two muscle layers: an inner circular layer that wraps around the esophagus and an outer longitudinal layer that runs the length of the tube. * Peristalsis: series of rhythmic muscular contractions and relaxations
(you can drink and eat while upside down!)
IV. Cardiac sphincter: a circular muscle located between the esophagus and the stomach. Prevents food from reentering esophagus. V. Stomach (food remains here 3-4 hours)
Location: the upper left side of the abdominal cavity, just below the diaphragm
Structure: elastic bag that is J-shaped when full and that lies in folds when empty.
It’s from several layers of smooth muscle. 1. Circular layer 2. Longitude layer 3. Diagonal layer
The churn when food is present. * Stomach “ growl” is when its empty so the smooth muscle contracts.
Digestive fluid: mucus, digestive enzymes, hydrochloric acid. Secreted by gastric glands. Gastric glands that open and close from gastric pits. those are in the inner lining of the stomach which is a thick mucous membrane made of epthielial cells.
Gastric fluid: 1. Pepsinogen (in active stomach secretion) CONVERTS TO pepsin (at low pH) 2. pepsin splits complex protein molecules into shorter chains of amino acids called peptides 3. Hydrochloric acid in the stomach not only ensures a low pH but also dissolves minerals and kills bacteria that enter the stomach along with food.*
*mucus protects the stomach lining from dissolving in hydrochloric acid and digestive enzymes.
Failure of this result into an ulcer. Stomach em5bgh. This is caused by bacteria that eat through epithelial cells.
In the end we get chyme. Then it goes into small intestine by peristalsis. VI. Pyloric sphincter: circular muscle between the stomach and the small intestine, regulates the flow of chyme. Each time the pyloric sphincter opens, about 5 to 15 mL of chyme moves into the small intestine, where it mixes with secretions from the liver and pancreas.
LIVER:
Location: to the right of the stomach
Function:
- storing glucose as glycogen
– making protein
– breaking down toxins (alcohol)
- secretes bile (vital to digestion of fat) breaks fat globules into small droplets, forming a milky fluid in which fats are suspended. This process exposes a greater surface area of fats to the action of digestive enzymes and prevents small fat droplets from rejoining into large globules.
GALLBLADDER: sac like organ, stores bile.
Bile gets here from the liver thro a y shaped duct, it gets concentrated until it’s released into the small intestine.
PANCREAS: a gland.
Location: behind the stomach, against the back wall of the abdominal cavity.
Function: * an endocrine gland, releases hormones that regulate blood sugar levels * Produces sodium bicarbonate, which neutralizes stomach acid. Makes chyme base.
Neutralizing stomach acid is important in order to protect the interior of the small intestine and to ensure that the enzymes secreted by the pancreas can function. * Produces enzymes that break down carbohydrates, proteins, lipids, and nucleic acids. These enzymes hydrolyze disaccharides into monosaccharides, fats into fatty acids and glycerol, and proteins into amino acids.
VII. Small intestine
Structure: coiled tube
Part one: duodenum
Part two: jejunum
Part three: ileum
Location: abdominal cavity.
Function: absorb nutrients
_
Step one [ Chyme enters > pancreas and liver secretion enter> intestinal mucous is released to protect the intestines walls from protein-digesting enzymes and the acidic chyme. ]
Step two [ Glands in the lining of the small intestine release enzymes that complete digestion by breaking down peptides into amino acids, disaccharides into monosaccharides, and fats into glycerol and fatty acids. ]
Step three [ amino acids, monosaccharides, glycerol, and fatty acids—are transferred into the circulatory system through blood and lymph vessels in the lining of the small intestine. ]
Villi (villus) (inside them there are capillaries and lacteals: tiny lymph vessels)
Location: small intestine lining
Structure: fingerlike projections with their own microvilli
Function: Nutrients are absorbed through this surface by means of diffusion and active transport. * Glycerol and fatty acids > lacteals> lymph vessels > bloodstream * Amino acids and monosaccharides > capillaries > liver
VIII. Large intestines (colon)
Part one: ascending colon,
Part two: transverse colon,
Part three: descending colon,
Part four: sigmoid colon. > rectum > anal canal.
SHIT HAPPENS: the absorption of water solidifies the mass. The solidified material is called feces.
As the fecal matter solidifies, cells lining the large intestine secrete mucus to lubricate the intestinal wall. This lubrication makes the passing of the feces less abrasive. Mucus also binds together the fecal matter, which is then eliminated through the anus.
IMMUNE SYSTEM
* Infectious disease: diseases that are caused by agents that invade the body. * Pathogen: any agent that causes disease. * Koch was the first to establish this. German doctor. His experiment: took bacteria from a diseased cow, grew it into colonies, and injected it into a healthy cow. The cow then got sick. * Koch postulate: 1. The pathogen must be present in an animal that has the disease and absent in healthy animals. 2. The pathogen must be isolated from the sick animal and grown in a laboratory 3. The isolated pathogen is injected into a healthy animal . said animal should get sick 4. Then again the pathogen must be taken from the healthy animal, isolated , injected into another healthy animal. Congratulations; you’ve got a disease. * Human diseases are caused by: * * Bacteria * Viruses * Fungus * Protists * Invertebrate * * Pathogens spread to human beings by: * * Air * Food * Water * Person to person contact * Animal bites.
* NON SEPCEFIC DEFENSE. * First line of defense:
Nonspecific defense, help protect the body from any type of pathogens. * Mucus membranes are epithelial tissues that protect the interior surfaces of the body that may be exposed to pathogens.
Function: secretes mucus, a sticky fluid that traps pathogens.
Location:
* Lines the respiratory (The passages of the respiratory tract are lined with cells that are covered with beating cilia. These cilia sweep mucus and pathogens up to the pharynx, where they are swallowed. Most swallowed pathogens are destroyed in the stomach by acids. * digestive systems, * the urethra, and the vagina. * Skin; a physical barrier against pathogens. Any break in the skin can allow pathogens to enter the body.
Releases: sweat, oils, and waxes. These substances contain chemicals that are toxic to many pathogens. For example, sweat contains lysozyme, an enzyme that destroys some bacteria.
* Second line of defense:
If a pathogen gets past the skin. The work against any type of pathogens.
* inflammatory response 1. damaged cells > histamine is released > blood flow to injury area increases> redness, swelling, warmth, pain > blood clotting. 2. Phagocytes (fluid and WBC) pass from capillary wall to injury area, * Neutrophil. Circulates with blood, eats pathogens. * Macrophage. Engulf pathogens and cells debris. Stationed, doesn’t seek out trouble but it’ll get you if you come at it. * Natural killer cells. Large WBC. Attack pathogen infected cells. Pierces cell membrane of infected cell, cell bursts from all the water entering it. 3. Phagocytes eat, destroy pathogens and foreign objects 4. Injury heals.
* Proteins * Complement system. Circulate blood. Activate when pathogen is present. Make a ring around infected cells and puncture their membrane. * Interferon. Released by infected cells, alerts other cells to make a protein that helps the cell fight the infection.
* Temperature response
Fever: Body temperature increases above the norm (37c).
Some pathogens trigger this. Midrate fever slows bacterial and viral growth and promote WBC activity.
Too high a fever is harmful. 39c destroys cell protein. 41c causes death.
* SPECEFIC DEFENSE. * immune system: the cells and tissues that recognize and attack foreign substances in the body, provides the body’s specific defenses. * Functions: fight pathogens stops the growth and spread of cancers.
Made up of: * WBC (lymphocytes) * Several tissues:
Part of the immune system | Type | location | function | Bone marrow | Soft material | Inside long bones, ex. femur | Makes new lymphocytes. Makes : B Cells (develop here) and T Cells | Thymus | gland | Above the heart | Helps produce a special kind of lymphocyte. T Cells finish their development here. | Lymph nodes | nodes | Throughout the body. Along the vessels of the lymphatic system | gathers and filters the fluid, called lymph, that leaksfrom the circulatory system. collect pathogens fromthe lymph and expose them to lymphocytes. | Spleen | Organ | | stores healthy blood cells,breaks down aging red blood cells, and helps develop lymphocytes and other types of WBC. collectspathogens from the blood, and the lymphocytes in the spleen attack these trapped pathogens. | Tonsils and adenoids | Lymph tissue | Nose and throat | |
Recognizing pathogens.
* Lymphocytes can provide specific defense because they recognize foreign invaders. * How lymphocytes recognize pathogens: * Has unique receptor proteins all over the surface of its cell membrane * These receptor proteins recognize and bind to antigens that match their three-dimensional shape * All of the receptors on an individual lymphocyte are the same shape or type and thus bind to the same type of antigens. * Body makes a lot of different lymphocytes, with different receptors. * Antigen: any substance that the immune system can recognize and react with.
-pathogens or -parts of pathogens, -bacterial toxins, -insect venom, -pollen
-any molecule that is not a natural part of an individual’s body, such as that from transplanted tissue or transfused blood of an incompatible type, can act as a foreign antigen
Antigens cover pathogens.
* Antigens cause lymphocytes to react.
Lymphocyte recognizes antigen > binds to antigen > specific attack.
This reaction is called immune response.
Immune
response
Require helper T cells
Part one: cell mediated immune response
Part two: humoral immune response
~
Step one: macrophage engulfs a pathogen
Step two: macrophage then displays fragments of the pathogen’s antigens on the surface of its own cell membrane
Step three: macrophage binds to a helper T cell with a receptor matching this antigen
Step four: macrophage releases a cytokine called interleukin-1
Step five: The release of interleukin-1 by the macrophage activates more helper T cells, which then release a second cytokine, interleukin-2.
~ Cytokines are proteins that can affect the behavior of other immune cells.
Cell mediated immune response
Humoral immune system
Primary and secondary immune response
Immunity: the ability of the body to resist disease.
To get immunity: * Get the disease, undergo primary response, survive * Vaccination: The introduction of antigens into the body to cause immunity. * vaccine is a solution that contains a dead or weakened pathogen or material from a pathogen. However, the antigens are still present, so the body produces a primary immune response to the antigens in the vaccine. The memory cells that remain after the primary immune response can provide a quick secondary immune response if the antigen ever enters the body again.
Problems with the immune system
Sometimes, the immune system reacts to otherwise harmless antigens in ways that can be harmful. 1. Allergies: physical response to an antigen
Possible causes: include pollen, animal dander (flakes of skin), dust mites, food, and fungal spores.
Symptoms: runny nose, sneezing, watery eyes, or itchy swellings of the skin 2. Asthma : respiratory disorder that causes the bronchioles (airways of the lungs) to narrow. 3. Autoimmune disease : disease in which the immune system attacks the organism’s own cells
Lymphocytes that recognize and react to the body’s own cells are usually eliminated during development, before they become functional.
Respiratory system
Function: exchange gases with the cardiovascular system
External respiration: exchange of gases between the atmosphere and the blood.
Internal respiration: exchange of gases between the blood and cells of the body. * Oxygen is used by cells to breakdown glucose and make ATP * Excess carbon dioxide produced as a waste product of aerobic respiration is toxic to cells and is removed from the cells by internal respiration.
Endocrine system:
Hormones: chemical messengers that coordinate the body’s activates. Substances secreted by cells that act to regulate the activity of other cells in the body. They are part of the endocrine system and they are slow acting but have a longer affect than neurotransmitters.
Functions:
* regulate growth, development, behavior, and reproduction. * Maintain homeostasis * Regulate metabolism and water and mineral balance * Respond to external stimuli * Exocrine glands: secrete substances ( water/enzymes/ mucus) through tube like ducts. * The ducts transport the substances to specific locations inside and outside the body.
Ex. Liver, sweat glands, mucus glands, salivary glands, other digestive glands
The endocrine system consists of:
* Endocrine glands: ductless organs …show more content…
that secret and make hormones either in the bloodstream or into extra cellular fluid
* Another hormones source: specialized cells in: brain, stomach, liver, small intestines, heart, and others.
__
Target cells: specific cells to which a hormone travels to produce a specific effect.
^ have receptors: proteins that bind specific signal molecules that cause the cell to respond.
(Found in: cell membrane/ cytoplasm/ nucleus of the cell)
How they work? 1. Each receptor binds to a specific hormone. 2. a hormone binds to a receptor 3. the binding triggers events that lead to changes within the cell.
__
second messenger is a molecule that initiates changes inside a cell in response to the binding of a specific substance to a receptor on the outside of a cell.
Urinary system:
Functions:
1. Maintains homeostasis by regulating the content of water and other substances in blood. 2. Removes waste.
Excretion: the process of removing metabolic waste.
Main waste products the need to be eliminated: * Carbon dioxide(from cellular respiration) removed by lungs * Nitrogenous compounds (from the breakdown of proteins) removed by kidneys
Ex. Urea: nitrogenous compound made by the liver.
Formation of urea: 1. Ammonia (nitrogenous waste) very toxic. Cell harming. Is in blood. 2. Blood is filtered from ammonia in the liver 3. Liver converts ammonia into urea 4. Urea enters blood stream then finds its way to kidneys 5. Urea is removed by kidneys
Organs in this system: 1. Kidneys:
Shape: bean shaped the size of a fist
Location: one behind the liver, one behind the stomach
Function: regulate the chemical composition of the blood
Structure:
- renal cortex (outermost portion of the kidney) 1/3 of kidney mass
- renal medulla (inner 2/3s of the kidney) consists of structures that carry urine, which empties into:
-renal pelvis (funnel shaped structure in the center of the kidney)
__
Blood flow: * Blood enters from: renal artery (transports waste and nutrients)
These nutrients are used by the kidney cells to carry out their life process.
Ex. Of a process: removal of waste. * Blood leaves from: renal vein: transports the filtered blood back to the heart.
__
NEPHRONS: the functional part of the kidneys
Shape: tiny tubes
Location: the kidneys
Function: making urine
Urine: amber colored liquid, its substances removed by the kidneys from the blood (water, toxins, urea, salt, and minerals: those remain in distal convoluted tubules)
All urine from all DCT goes to collecting duct. Osmosis occurs, 99% of water returns to blood.
Structure of nephron: * Bowman’s capsule: at an end of a nephron, cup shaped capsule surrounding a tight ball of capillaries that retains cells and large molecules in the blood and passes wastes dissolved in water through the nephron. * -------------------------------------------------
Glomerulus: a fine network of capillaries within the Bowman capsule. The capillaries come from arterioles.
THREE MAIN PROCESSES IN NEPHRONS: 1. Filtration: Materials from the blood are forced out of the glomerulus and into the Bowman’s capsule. 2. Reabsorption:
Water: goes back by osmosis (75% of it)
Minerals (sodium, calcium, potassium) / glucose: return by active transport 3. Secretion: substances pass from the blood into the filtrate.
__
Elimination of urine:
-------------------------------------------------
Collecting duct > renal pelvis> ureter> urinary bladder> urethra.
Excretory organs:
Lungs: detoxification, altering harmful substances so that they are not poisonous.
Skin: excretes water, salts, small amounts of nitrogen wastes, and other substances in sweat.
__
------------------------------------------------- excretion : correctly refers to the process during which substances must pass through a membrane to leave the body.
Digestive system: Is made up of: The digestive system is made up of the gastrointestinal tract, salivary glands, the liver, gallbladder, and pancreas.
Digestion: process of breaking down food into molecules the body can use.
Occurs in: * Gastrointestinal tract or Digestion tract: long, winding tube which begins at the mouth and winds through the body to the anus. * Organs in this tract carry out digestion
With aid of secretion from ducts that are not part of this tract.
The process: 1. Mechanical and chemical breakdown of food 2. Absorption of nutrients 3. Elimination of waste
I. Mouth: * incisors cut the food * molars grind the food the tongue keeps the food between the chewingness and moves it around against the roof of the mouth *hard palate* which is bony and hard. * Salivary amylase begins the chemical digestion of carbohydrates by breaking down some starch into the disaccharide maltose.
So food gets chewed, moistened and rolled into a bolus here.
Salivary glands: * Produce: saliva .. a mixture of water, mucus, and a digestive enzyme called salivary amylase. * Location: tiny glands in the lining of the mouth and three other larger glands.
II. Pharynx : open area that begins at the back of the mouth, serves as a passageway for both air and food. * Epiglottis: a flap of tissue, prevents food from entering the trachea, or windpipe, during swallowing. III. Esophagus: connects the pharynx with the stomach.
Structure: muscular tube approximately 25 cm long consists of two muscle layers: an inner circular layer that wraps around the esophagus and an outer longitudinal layer that runs the length of the tube. * Peristalsis: series of rhythmic muscular contractions and relaxations
(you can drink and eat while upside down!)
IV. Cardiac sphincter: a circular muscle located between the esophagus and the stomach. Prevents food from reentering esophagus. V. Stomach (food remains here 3-4 hours)
Location: the upper left side of the abdominal cavity, just below the diaphragm
Structure: elastic bag that is J-shaped when full and that lies in folds when empty.
It’s from several layers of smooth muscle. 1. Circular layer 2. Longitude layer 3. Diagonal layer
The churn when food is present. * Stomach “ growl” is when its empty so the smooth muscle contracts.
Digestive fluid: mucus, digestive enzymes, hydrochloric acid. Secreted by gastric glands. Gastric glands that open and close from gastric pits. those are in the inner lining of the stomach which is a thick mucous membrane made of epthielial cells.
Gastric fluid: 1. Pepsinogen (in active stomach secretion) CONVERTS TO pepsin (at low pH) 2. pepsin splits complex protein molecules into shorter chains of amino acids called peptides 3. Hydrochloric acid in the stomach not only ensures a low pH but also dissolves minerals and kills bacteria that enter the stomach along with food.*
*mucus protects the stomach lining from dissolving in hydrochloric acid and digestive enzymes.
Failure of this result into an ulcer. Stomach em5bgh. This is caused by bacteria that eat through epithelial cells.
In the end we get chyme. Then it goes into small intestine by peristalsis. VI. Pyloric sphincter: circular muscle between the stomach and the small intestine, regulates the flow of chyme. Each time the pyloric sphincter opens, about 5 to 15 mL of chyme moves into the small intestine, where it mixes with secretions from the liver and pancreas.
LIVER:
Location: to the right of the stomach
Function:
- storing glucose as glycogen
– making protein
– breaking down toxins (alcohol)
- secretes bile (vital to digestion of fat) breaks fat globules into small droplets, forming a milky fluid in which fats are suspended. This process exposes a greater surface area of fats to the action of digestive enzymes and prevents small fat droplets from rejoining into large globules.
GALLBLADDER: sac like organ, stores bile.
Bile gets here from the liver thro a y shaped duct, it gets concentrated until it’s released into the small intestine.
PANCREAS: a gland.
Location: behind the stomach, against the back wall of the abdominal cavity.
Function: * an endocrine gland, releases hormones that regulate blood sugar levels * Produces sodium bicarbonate, which neutralizes stomach acid. Makes chyme base.
Neutralizing stomach acid is important in order to protect the interior of the small intestine and to ensure that the enzymes secreted by the pancreas can function. * Produces enzymes that break down carbohydrates, proteins, lipids, and nucleic acids. These enzymes hydrolyze disaccharides into monosaccharides, fats into fatty acids and glycerol, and proteins into amino acids.
VII. Small intestine
Structure: coiled tube
Part one: duodenum
Part two: jejunum
Part three: ileum
Location: abdominal cavity.
Function: absorb nutrients
_
Step one [ Chyme enters > pancreas and liver secretion enter> intestinal mucous is released to protect the intestines walls from protein-digesting enzymes and the acidic chyme. ]
Step two [ Glands in the lining of the small intestine release enzymes that complete digestion by breaking down peptides into amino acids, disaccharides into monosaccharides, and fats into glycerol and fatty acids. ]
Step three [ amino acids, monosaccharides, glycerol, and fatty acids—are transferred into the circulatory system through blood and lymph vessels in the lining of the small intestine. ]
Villi (villus) (inside them there are capillaries and lacteals: tiny lymph vessels)
Location: small intestine lining
Structure: fingerlike projections with their own microvilli
Function: Nutrients are absorbed through this surface by means of diffusion and active transport. * Glycerol and fatty acids > lacteals> lymph vessels > bloodstream * Amino acids and monosaccharides > capillaries > liver
VIII. Large intestines (colon)
Part one: ascending colon,
Part two: transverse colon,
Part three: descending colon,
Part four: sigmoid colon. > rectum > anal canal.
SHIT HAPPENS: the absorption of water solidifies the mass. The solidified material is called feces.
As the fecal matter solidifies, cells lining the large intestine secrete mucus to lubricate the intestinal wall. This lubrication makes the passing of the feces less abrasive. Mucus also binds together the fecal matter, which is then eliminated through the anus.
IMMUNE SYSTEM
* Infectious disease: diseases that are caused by agents that invade the body. * Pathogen: any agent that causes disease. * Koch was the first to establish this. German doctor. His experiment: took bacteria from a diseased cow, grew it into colonies, and injected it into a healthy cow. The cow then got sick. * Koch postulate: 1. The pathogen must be present in an animal that has the disease and absent in healthy animals. 2. The pathogen must be isolated from the sick animal and grown in a laboratory 3. The isolated pathogen is injected into a healthy animal . said animal should get sick 4. Then again the pathogen must be taken from the healthy animal, isolated , injected into another healthy animal. Congratulations; you’ve got a disease. * Human diseases are caused by: * * Bacteria * Viruses * Fungus * Protists * Invertebrate * * Pathogens spread to human beings by: * * Air * Food * Water * Person to person contact * Animal bites.
* NON SEPCEFIC DEFENSE. * First line of defense:
Nonspecific defense, help protect the body from any type of pathogens. * Mucus membranes are epithelial tissues that protect the interior surfaces of the body that may be exposed to pathogens.
Function: secretes mucus, a sticky fluid that traps pathogens.
Location:
* Lines the respiratory (The passages of the respiratory tract are lined with cells that are covered with beating cilia. These cilia sweep mucus and pathogens up to the pharynx, where they are swallowed. Most swallowed pathogens are destroyed in the stomach by acids. * digestive systems, * the urethra, and the vagina. * Skin; a physical barrier against pathogens. Any break in the skin can allow pathogens to enter the body.
Releases: sweat, oils, and waxes. These substances contain chemicals that are toxic to many pathogens. For example, sweat contains lysozyme, an enzyme that destroys some bacteria.
* Second line of defense:
If a pathogen gets past the skin. The work against any type of pathogens.
* inflammatory response 1. damaged cells > histamine is released > blood flow to injury area increases> redness, swelling, warmth, pain > blood clotting. 2. Phagocytes (fluid and WBC) pass from capillary wall to injury area, * Neutrophil. Circulates with blood, eats pathogens. * Macrophage. Engulf pathogens and cells debris. Stationed, doesn’t seek out trouble but it’ll get you if you come at it. * Natural killer cells. Large WBC. Attack pathogen infected cells. Pierces cell membrane of infected cell, cell bursts from all the water entering it. 3. Phagocytes eat, destroy pathogens and foreign objects 4. Injury heals.
* Proteins * Complement system. Circulate blood. Activate when pathogen is present. Make a ring around infected cells and puncture their membrane. * Interferon. Released by infected cells, alerts other cells to make a protein that helps the cell fight the infection.
* Temperature response
Fever: Body temperature increases above the norm (37c).
Some pathogens trigger this. Midrate fever slows bacterial and viral growth and promote WBC activity.
Too high a fever is harmful. 39c destroys cell protein. 41c causes death.
* SPECEFIC DEFENSE. * immune system: the cells and tissues that recognize and attack foreign substances in the body, provides the body’s specific defenses. * Functions: fight pathogens stops the growth and spread of cancers.
Made up of: * WBC (lymphocytes) * Several tissues:
Part of the immune system | Type | location | function | Bone marrow | Soft material | Inside long bones, ex. femur | Makes new lymphocytes. Makes : B Cells (develop here) and T Cells | Thymus | gland | Above the heart | Helps produce a special kind of lymphocyte. T Cells finish their development here. | Lymph nodes | nodes | Throughout the body. Along the vessels of the lymphatic system | gathers and filters the fluid, called lymph, that leaksfrom the circulatory system. collect pathogens fromthe lymph and expose them to lymphocytes. | Spleen | Organ | | stores healthy blood cells,breaks down aging red blood cells, and helps develop lymphocytes and other types of WBC. collectspathogens from the blood, and the lymphocytes in the spleen attack these trapped pathogens. | Tonsils and adenoids | Lymph tissue | Nose and throat | |
Recognizing pathogens.
* Lymphocytes can provide specific defense because they recognize foreign invaders. * How lymphocytes recognize pathogens: * Has unique receptor proteins all over the surface of its cell membrane * These receptor proteins recognize and bind to antigens that match their three-dimensional shape * All of the receptors on an individual lymphocyte are the same shape or type and thus bind to the same type of antigens. * Body makes a lot of different lymphocytes, with different receptors. * Antigen: any substance that the immune system can recognize and react with.
-pathogens or -parts of pathogens, -bacterial toxins, -insect venom, -pollen
-any molecule that is not a natural part of an individual’s body, such as that from transplanted tissue or transfused blood of an incompatible type, can act as a foreign antigen
Antigens cover pathogens.
* Antigens cause lymphocytes to react.
Lymphocyte recognizes antigen > binds to antigen > specific attack.
This reaction is called immune response.
Immune
response
Require helper T cells
Part one: cell mediated immune response
Part two: humoral immune response
~
Step one: macrophage engulfs a pathogen
Step two: macrophage then displays fragments of the pathogen’s antigens on the surface of its own cell membrane
Step three: macrophage binds to a helper T cell with a receptor matching this antigen
Step four: macrophage releases a cytokine called interleukin-1
Step five: The release of interleukin-1 by the macrophage activates more helper T cells, which then release a second cytokine, interleukin-2.
~ Cytokines are proteins that can affect the behavior of other immune cells.
Cell mediated immune response
Humoral immune system
Primary and secondary immune response
Immunity: the ability of the body to resist disease.
To get immunity: * Get the disease, undergo primary response, survive * Vaccination: The introduction of antigens into the body to cause immunity. * vaccine is a solution that contains a dead or weakened pathogen or material from a pathogen. However, the antigens are still present, so the body produces a primary immune response to the antigens in the vaccine. The memory cells that remain after the primary immune response can provide a quick secondary immune response if the antigen ever enters the body again.
Problems with the immune system
Sometimes, the immune system reacts to otherwise harmless antigens in ways that can be harmful. 1. Allergies: physical response to an antigen
Possible causes: include pollen, animal dander (flakes of skin), dust mites, food, and fungal spores.
Symptoms: runny nose, sneezing, watery eyes, or itchy swellings of the skin 2. Asthma : respiratory disorder that causes the bronchioles (airways of the lungs) to narrow. 3. Autoimmune disease : disease in which the immune system attacks the organism’s own cells
Lymphocytes that recognize and react to the body’s own cells are usually eliminated during development, before they become functional.
Respiratory system
Function: exchange gases with the cardiovascular system
External respiration: exchange of gases between the atmosphere and the blood.
Internal respiration: exchange of gases between the blood and cells of the body. * Oxygen is used by cells to breakdown glucose and make ATP * Excess carbon dioxide produced as a waste product of aerobic respiration is toxic to cells and is removed from the cells by internal respiration.