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Lab 7: Vertebrate Anatomy: Difference between revisions
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→Digestive, Urogenital, Circulatory and Respiratory Anatomy of the Fetal Pig
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The <u>stomach</u> lies on the left side of the upper abdomen. Food enters the mouth, travels through the pharynx, and when swallowed enters the <u>esophagus</u>. The esophagus is an easily compressible tube that lies immediately dorsal to the trachea. The esophagus traverses the thoracic cavity, and then passes through an opening in the diaphragm to enter the abdominal cavity. You will find these organs later in the dissection.<br> | The <u>stomach</u> lies on the left side of the upper abdomen. Food enters the mouth, travels through the pharynx, and when swallowed enters the <u>esophagus</u>. The esophagus is an easily compressible tube that lies immediately dorsal to the trachea. The esophagus traverses the thoracic cavity, and then passes through an opening in the diaphragm to enter the abdominal cavity. You will find these organs later in the dissection.<br> | ||
The esophagus transports food to the stomach, which is a major site of protein digestion. Caudally, the stomach empties the semi-digested chyme into the <u>small intestine</u>. The most anterior part of the small intestine, the <u>duodenum</u>, receives bile synthesized by the liver and digestive enzymes from the <u>pancreas</u>. The pancreas is a lobulated structure somewhat lighter in color than the neighboring intestines. The main body of the pancreas lies in the loop of the duodenum. Carbohydrates, fats, and proteins are all digested in the small intestine. Although the long narrow <u>spleen</u> is not a digestive organ, its position, wedged between the stomach and the diaphragm, make discussion of it appropriate. In the pig and many other mammals, the spleen is quite muscular and can eject large quantities of blood into the circulation to correct sudden blood loss. The human spleen is not muscular so it cannot contract nor store a large quantity of blood. It functions as an important part of the immune system, but is not an essential organ, meaning humans can live without one if it must be removed due to trauma or disease. | The esophagus transports food to the stomach, which is a major site of protein digestion. Caudally, the stomach empties the semi-digested chyme into the <u>small intestine</u>. The most anterior part of the small intestine, the <u>duodenum</u>, receives bile synthesized by the liver and digestive enzymes from the <u>pancreas</u>. The pancreas is a lobulated structure somewhat lighter in color than the neighboring intestines. The main body of the pancreas lies in the loop of the duodenum. Carbohydrates, fats, and proteins are all digested in the small intestine. Although the long narrow <u>spleen</u> is not a digestive organ, its position, wedged between the stomach and the diaphragm, make discussion of it appropriate. In the pig and many other mammals, the spleen is quite muscular and can eject large quantities of blood into the circulation to correct sudden blood loss. The human spleen is not muscular so it cannot contract nor store a large quantity of blood. It functions as an important part of the immune system, but is not an essential organ, meaning humans can live without one if it must be removed due to trauma or disease. <br> | ||
Follow the course of the small intestine, which is supported by a membrane, the <u>mesentery</u>. The end of the small intestine joins the <u>large intestine</u> (colon), which is noticeably larger in cross section. At the juncture a short blind sac, the <u>caecum</u>, is formed. The large intestine is a site of water re-absorption. Follow its course through the posterior abdomen to its terminal portion, the <u>rectum</u>. You will not be able to see the rectum until you remove the pubic bone later in the dissection. Wastes leave the digestive system via the anus directly below the rectum.<br><br> | Follow the course of the small intestine, which is supported by a membrane, the <u>mesentery</u>. The end of the small intestine joins the <u>large intestine</u> (colon), which is noticeably larger in cross section. At the juncture a short blind sac, the <u>caecum</u>, is formed. The large intestine is a site of water re-absorption. Follow its course through the posterior abdomen to its terminal portion, the <u>rectum</u>. You will not be able to see the rectum until you remove the pubic bone later in the dissection. Wastes leave the digestive system via the anus directly below the rectum.<br><br> | ||
