{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Review - hillarys review - AnthroBio 364 Exam 2 Study Guide...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
AnthroBio 364 Exam 2 Study Guide: Digestion: - Starts in the mouth and continues in the stomach. - Nutrient absorption takes place in the small intestine while excretion of waste products occurs through the colon (large intestine) and rectum. - In the mouth, food is broken down into finer particles by the teeth, moistened and lubricated by saliva. - The saliva provides enzymes such as amylase that starts the digestion process. - Thereafter, the food is swallowed into the esophagus and carried by peristalsis to the stomach. - In the stomach some water, certain ions, and such drugs as asprin and ethanol are absorbed and transported into the blood. - In the stomach in response to the arrival of food, the gastric glands stimulated by the hormone gastrin secretes hydrochloric acid (HCI). - Once the contents of the stomach becomes liquefied, they pass into the duodenum, the first segment of the small intestine. Here, enzymes break down molecules of intact or partially digest carbohydrates, fats, and protein into monosaccharides, fatty acids and amino acids. - In addition, the liver secretes pepsinogen. - The liver secretes bile and stores in the gall bladder. - When food, especially when it contains fat, is stimulated by the hormone cholecystokinin, the gall bladder contracts and discharge its bile into the duodenum. - The bile contains bile acids, which, emulsify and dissolve the fat ingested fat into tiny droplets that can be more easily digested and absorbed. - The joint action of HCI and pepsinogen breaks down food into small particles and separates the bonds that keep together the carbohydrates, proteins and fats. - Undigested materials go from the small intestine to the large intestine and then to the rectum! - Function of the liver: o Stores and releases glucose: when the concentration of glucose in the blood drops between meals, the liver releases glucose to the blood by converting its glycogen stores to glucose and it converts certain amino acids into glucose. o Synthesis of proteins circulating the blood: albumin and many of the clotting factors necessary to prevent bleeding into tissues. o Secretion of bile: bile is the major route of excretion for cholesterol and is important in helping to absorb fat in the diet. o Detoxifying ammonia: ammonia is a by-product of protein metabolism whereby ammonia is converted into urea which is excreted by the kidney. o Synthesis of cholesterol: cholesterol is important for cell membrane function but excessive amounts are bad. - Pancreas: o The pancreas is an oval shaped long, soft organ that lies beneath the stomach and is connected to the small intestine at the duodenum. It plays an important role in food digestion, secreting enzymes that break down fat, starch and proteins in the small intestine. - Functions of the pancreas:
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
o Secretes glucagons and insulin. It contains clusters of cells (islets of Langerhans) that secrete two hormones insulin and glucagon into the blood stream. They regulate the level of glucose in the blood.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}