The process of digestion can be fast, or can take some time depending on what a person has eaten. The time frame can also be affected by the person’s activity level. Food which is taken through the mouth is initially broken down by mechanical means. The teeth are responsible for grinding food, while the tongue assists the mixing of the food with saliva, which is secreted by the salivary glands, thereby initiating the chemical digestion of carbohydrates. This mechanically broken down food is now swallowed into the esophagus where the process of peristalsis pushes the food into the stomach. Once in the stomach, gastric juices which have been secreted into the stomach mix with the food and begin the enzymatic digestion of proteins. The food is then passed through the pyloric sphincter into the duodenum. The liver, gallbladder and pancreas are all located around the stomach, but do not affect the food until it is in the duodenum. These accessory organs are responsible for the following:
- Liver – produces bile, which emulsifies fat
- Gallbladder – stores bile and introduces it into the small intestine
- Pancreas – produces and secretes pancreatic juice, containing digestive enzymes and bicarbonate ions into the small intestine From the duodenum the food is moved into the small intestine, where it is mixed with bile and pancreatic juice. The small intestine is where the final enzymatic breakdown of food molecules occurs, and is the main site of nutrient absorption. From here the food is delivered to the large intestine where water and electrolytes are absorbed and feces are formed. This food will travel through the large intestine into the rectum which regulates the elimination of feces.
You May Also Find These Documents Helpful
-
The beginning of the digestive process starts with the smell and sight of food which activate the salivary glands. The mouth is the point at which food enters the digestive tract and continues the digestive process by chewing food. The food is then broken down into pieces and moistened by salivary glands which turn food into a bolus. The bolus goes down the pharynx into the esophagus which connects the pharynx to the stomach. The stomach is an organ that mixes food and secretes gastric juice. The bolus, once in the stomach, is mixed into a semiliquid mass called chime. The stomach is close together with the liver and pancreas but does not get assistance from these organs. The chime then enters…
- 251 Words
- 2 Pages
Good Essays -
When we vomit, the acidic nature of our stomach contents becomes immediately apparent both from the taste and from the burning sensation in our throats. The purpose of this acidity is to kill any bacteria we swallow with our food. In the stomach, digestive enzymes and a muscular churning action combine to reduce our food to a thick liquid called chyme. Chyme exits the stomach through a second sphincter and enters the small intestine. Typically, it takes the stomach about 4 hours to process a meal. The small intestine is about 20 feet long. In the duodenum, the first foot of the small intestine, digestion continues with the breakdown of proteins, fats, carbohydrates, and nucleic acids. Some of the digestive enzymes at work in the duodenum are made by the small intestine itself. Others are made by the pancreas. Pancreatic enzymes play an important role in neutralizing food, which arrives from the stomach in a highly acidic condition. In addition, the small intestine receives bile, a substance that is produced in the liver and stored in the gall bladder. Bile is an emulsifier?it breaks fats into tiny droplets that are more easily attacked by enzymes. Beyond the duodenum, the rest of the small intestine functions primarily in absorbing nutrients into the body. In order to be able to do this efficiently?that is, rapidly?the small intestine has a huge surface area. It is covered with numerous fingerlike projections called villi, each of which is in turn covered with tiny little projections called microvilli. Flattened, the small intestine would fill the area of a tennis court! Digested nutrients are absorbed across the surface of the small intestine into capillaries found inside each villus.…
- 4740 Words
- 19 Pages
Better Essays -
• What factors affect the amount of time it takes for foods to travel through the digestive tract?…
- 483 Words
- 2 Pages
Good Essays -
The gastrointestinal tract starts with the mouth, which leads to the gullet via the stomach, small intestine, large intestine, and ends at the anus. In due course of the journey, the ingested food is broken down by both physical and chemical means to release nutrients which are absorbed into the blood stream. The ingested food is physically broken down in the mouth by chewing so as to reduce its size for increased surface area over which enzymatic reaction will take place. Enzymatic reaction is known as digestion and this is defined as the chemical breakdown of the ingested complex food molecules by the action of biological enzymes, into simplest form that can be absorbed into the blood stream and assimilated into living cells. In human beings, various components of the ingested food are digested and absorbed at various sections of the alimentary canal .…
- 1938 Words
- 8 Pages
Better Essays -
The glands in the stomach lining produce stomach acid, called gastric acid, and an enzyme that digests protein. The pancreas produces a juice containing several enzymes that break down carbohydrates, fats, and proteins in food. The pancreas delivers digestive juice to the small intestine through small tubes called ducts.…
- 664 Words
- 3 Pages
Good Essays -
Digestion begins in the mouth. A brain reflex triggers the flow of saliva when we see or even think of food. Saliva moistens the food while the teeth chew it up and make it easier to swallow. Amylase, which is the digestive enzyme, found in saliva, starts to break down starch into simpler sugars before the food even leave the mouth. The nervous pathway involved in salivary excretion requires stimulation of receptors in the mouth, sensory impulses to the brain stem and parasympathetic impulses to salivary glands. Swallowing his food happens when the muscles in his tongue and mouth move the food into his pharynx. The pharynx, which is the passage way for food and air, a small flap of skin called the epiglottis closes over the pharynx to prevent food from entering the trachea and causing choking. For swallowing to happen correctly a combination of 25 muscles must all work together at the same time. After being chewed and swallowed the food enters the esophagus or gullet is the muscular tube in vertebrates through which ingested food passes from the throat to the stomach. It connects the pharynx, which is the body cavity that is common to both the digestive and respiratory systems behind the mouth, with the stomach, where the second stage of digestion is initiated. The esophagus is a long tube that runs from the mouth to the stomach. It uses rhythmic wave like muscle movements called peristalsis to force food from the throat into the…
- 1364 Words
- 6 Pages
Good Essays -
The Digestive System is the name given to the sequential process that our bodies perform when ingesting food, and the breaking down of macromolecules into micromolecules so that the body can absorb it’s nutrients into the bloodstream and it’s cellular system to obtain energy for cellular respiration, and the excretion all indigestible waste products. This happens within the digestive tract, which starts at the Mouth or Oral cavity and ends at the Anus. (Reference Appended image 1,’ The Human digestive system and associated organs). The molecules of food that we eat are generally Polymers, i.e., large, complex Molecules that are composed of long chains of Monomers. Polymers are insoluble and therefore cannot be absorbed into our bloodstream and need to be assimilated into different absorptive products. Polymers have to be hydrolysed into smaller, soluble molecules. This process happens during the process of digestion. Food is broken down by mechanical or chemical means (Hydrolysis) and this process is aided by Enzymes. Enzymes are biological, process catalysing Proteins which massively speed up the breaking down of compound molecules into micromolecules to allow nutritional absorption. All digestive Enzymes are Hydrolytic, i.e., a water molecule is added to allow compound molecular breakdown and separation. All Enzymes have a unique shape to their ‘active site’ allowing only the target substrate to bond for biological processing. Enzymes have optimum operating requirements and can denature if the temperature becomes too warm or the environment too acidic or alkaline. Digestive Enzyme secretion is regulated by both the nervous and the hormonal systems. Hormones are a chemical substance signalling system that communicates from one set of cells to another set, the target cells, which will then trigger enzyme secretion.…
- 1910 Words
- 8 Pages
Better Essays -
The digestive system works like an assembly line in reverse. Carbohydrates, fats and proteins are progressively broken down into smaller molecules that can be used by the body. This system extracts needed nutrients and gets rid of any unnecessary wastes. Structurally, the digestive system consists of the long tube, the gastrointestinal (GI) tract that serves as the direct pathway for what you eat and excrete. Along the way, various accessory organs help with the mechanical breakdown and the chemical digestion of food. Mechanical digestion involves physically mashing or tearing the bites of food we put in our mouths. We normally think of mechanical digestion occurring in the mouth, but there are other features of your GI tract that also help mash up your food. As what you consume is being smashed, chemical digestion also begins. Enzymes break fats, carbohydrates and proteins into their building blocks so they can be used by the body. Once these molecules are broken down, they can become the raw material for the production of the body’s energy currency, adenosine triphosphate (ATP).…
- 1178 Words
- 4 Pages
Good Essays -
The mouth is the first stage of the gastrointestinal tract and is arranged with numerous structures that aid in the digestion of food. These include the tongue, teeth, and salivary glands and begin the first processes of digestion.…
- 552 Words
- 3 Pages
Good Essays -
A burger is broken down mechanically by biting into it. The food in the mouth sets off salivary glands that secrete salivary amylase, which breaks down amylase in the burger. When the food is broken down enough, the tongue shapes the food in a bolus, or a ball. The bolus is pushed back to the pharynx at the back of the throat. The food stimulates the opening of the flap so the good goes down the esophagus, rather than the windpipe. Because of peristalsis, rhythmic waves created by muscles in the throat, the food slides easily down the digestive tract. Salivary amylase continues to break down the starch all the way down the esophagus.…
- 362 Words
- 1 Page
Good Essays -
The teeth are used to physically break down food material before it is swallowed. The churning of food in the stomach then continues the mechanical breakdown process.…
- 5068 Words
- 21 Pages
Powerful Essays -
Digestion is an important process needed for maintaining and providing energy to living organisms. Throughout the digestion process, food is broken down into small molecules, where it can be absorbed easily. There are many organs that aid in this complex task. Ingestion, digestion, and absorption are the three necessary steps of the digestive process.…
- 349 Words
- 2 Pages
Satisfactory Essays -
Mouth and oral cavity: Teeth mechanically break food into small pieces (mastication); saliva lubricates food and amylase digests starch into maltose.…
- 373 Words
- 2 Pages
Good Essays -
Basically, digestion of carbohydrate involves conversion of the large molecules of carbohydrates like di-saccharides and polysaccharides into simple mono-saccharide molecules which can be easily absorbed by the body. The first step of digestion is the moment we put the food in mouth. As we chew the food, the saliva released by the salivary glands of the mouth starts its work of breaking up of the carbohydrates. This is possible because of the presence of a special enzyme named amylase in the saliva. Then we swallow the food and it goes to the stomach. Here the digestive acids secreted by the glands of the stomach play a major role in processing the carbohydrate molecules further. The digestive enzyme of the stomach also helps in this work but they do not have much significant role in digestion in the stomach.…
- 777 Words
- 4 Pages
Good Essays -
In mammals, food enters the mouth, being chewed by teeth, with chemical processing beginning with chemicals in the saliva from the salivary glands. This is called mastication. Then it travels down the esophagus into the stomach, where hydrochloric acid kills most contaminating microorganisms and begins mechanical break down of some food (e.g., denaturation of protein), and chemical alteration of some. The hydrochloric acid also has a low pH, which is great for enzymes. After some time (typically an hour or two in humans, 4–6 hours in dogs, somewhat shorter duration in house cats, ...), the resulting thick liquid is called chyme. Chyme will go through the small intestine, where 95% of absorption of nutrients occurs, through the large intestine, and are excreted duringdefecation.[1]…
- 640 Words
- 3 Pages
Satisfactory Essays