As teeth tear, cut, and grind food, three pairs of glands make saliva. These salivary glands are located in front of the ears, under the lower jaw, and under the tongue. Tiny tubes carry the saliva from the salivary glands to the mouth.
The esophagus of an adult is about 25 centimeters long. Muscles in the esophagus contract and relax to push swallowed food down toward the stomach. The process is something like squeezing toothpaste out of a tube.
Stomach is a bag-like organ with muscular walls. Stomach muscles squeeze and mix food with digestive juice make in the stomachs lining. The juice changes the food, which stays in the stomach for two to four hours. When the food leaves the stomach, it is a thick liquid.
The liquid food is pushed into the small intestine, a curled-up tube. If stretched out, an adult’s small intestine would be about 7 meters long. Most digestion takes place in the three to six hours that food stays in the small intestine. Juices made in the lining of the small intestine and other organs mix with food. The juices change the food into nutrients. The nutrients pass through the thing walls of blood vessels in the intestinal lining. Blood carries the nutrients to body cells.The parts of food that cannot be digested move to the large intestine, along with some liquid. The large intestine removes much or the liquid and stores the resulting solid waste until it leaves the body.
References:
http://www.walgreens.com/adamHtml/bodyguides/reftext/images/Peristalsis.jpg. (n.d.). Google. Retrieved October 18, 2012, from http://www.google.com.lb/imgres
http://2.bp.blogspot.com/ Stomach-Digestion.jpg. (n.d.). Google. Retrieved October 18, 2012, from management-of-disease.blogspot.com/2011_02_04_archive.
http://www.umm.edu/graphics/images/en/8710.jpg. (n.d.). Google. Retrieved October 18, 2012, from www.umm.edu/patiented/articles
http://www.infoplease.com/images/ency142mouth001.gif. (n.d.). Google. Retrieved October 18, 2012, from www.infoplease.com/dk/encyclopedia/mouth
Cooney, T. M. (2003). Scott Foresman science: grade 4. Glenview, Ill.: Scott, Foresman.
Questions:
Where are the three glands that make the saliva located at?
How long is the esophagus of an adult person?
- The three glands are located in front of the ears, under the lower jaw, and under the tongue.
ReplyDelete- The esophagus of an adult is about 25 centimeters long.
1) salivary glands are located; front of the ears, under the lower jaw, and under the tongue.
ReplyDelete2) The esophagus of an adult is around 25 centimeters long.