How the Digestive System Works
small intestine
A ring of muscle at the end of the stomach controls the flow of food by opening and closing every few minutes to allow the liquid food to flow into the ____, a very long, coiled, tube-like organ.
gall bladder
A storage sac called the ___ holds the bile that is produced in the liver.
esophagus
After being swallowed, the food passes into a muscular tube called the ____, which connects the mouth to the stomach.
rectum
At this point in the process, no more digestion occurs Water and salts are taken out of the waste material in the large intestine. The remaining solid wastes, called feces, are the end product of digestion and are stored in the ______.
salivary glands
Digestion begins as soon as food enters thew mouth where the teeth and tongue work together to physically break down the food into smaller pieces. As chewing takes place , a secretion from the _____ softens and lubricates the food.
peristalsis
Food in the esophagus is squeezed toward the stomach by contraction and relaxation of the muscles in the esophagus. This muscular action, known as _____, also helps to move food through the rest of the digestive tract.
bile
Food remains in this organ for about four to six hours and is mixed with digestive liquids, such as ___, a mixture of enzymes and acids that chemically break down food, which is broken into smaller pieces through a churning action of three layres of muscles in the stomach which is lined and protected from the strong digestive juices by a layer of mucus
stomach
Food takes about six seconds to travel from the mouth to the ___, a j shaped sac that stores and further digests the food.
mechanical
In the digestive system, food undergoes two kinds of digestion. ____ occurs as the food is broken into smaller pieces.
large intestine
Materials that are not digested move into ____, which is a wider but shorter tube than the small intestine
chemical
Mechanical digestion prepares the food for ___ digestion, which is the process by which foods are chemically changed into simpler substances.
pancreas
Pancreatic juice is another digestive juice added in the small intestine. It is produced in the ____.
enzymes
Saliva contains ______, substances that speed up chemical reactions and break down large starch molecules into smaller molecules of sugar.
tongue
The ____ helps push food to the back of the mouth where it is swallowed.
gastric juice
The final steps of digestion occur in the small intestine. One type of digestive liquid that is added here is called___, which is produced in the liver and breaks down fats in foods.
villi
The nutrients from the digested food are then absorbed into the bloodstream through tiny finger-like structures called ____, that line the inner wall of the small intestines. Nutrients from the digested food are carried by the blood from this to the cells of the body
appendix
There is a little pouch called ____, located where the small intestine joins the large intestine. It has no known purpose in our bodies, but it can sometimes become infected and have to be removed
saliva
This secretion from the salivary glands is called ____.
intestinal juice
____ is made in the walls of the small intestine, works together with the pancreatic juice to chemically break down the food
digestion
____ is the process by which food is broken down into substances that can be used by the cells of the body