BIO 211 Hybrid Discussion questions Chapter 17
Chapter 17 #1 Please answer the following about Gastric Juice production in the digestive system. Name the four (4) gastric cells; for each cell type give the name and function for each the chemical substance(s) it secretes.
A) Mucous cells- These cells secrete mucus, which protects the mucosa from the action of acid and digestive enzymes.
B) Parietal cells- They secrete hydrochloric acid (HC) and intrinsic factor. Intrinsic factor is necessary for the absorption of vitamin B12 in the small intestine. Hydrochloric acid is a strong acid that helps to break down food. The g-cells produce gastrin, a hormone that triggers the production of hydrochloric acid by the parietal cells.
C) Chief cells- They secrete pepsinogen, the inactive form of pepsin. Pepsin is a protease, an enzyme that breaks down proteins.
D) Enteroendocrine cells- secrete several hormones that distribute into the blood vessels. One important hormone, gastrin, stimulates other glands in the stomach to increase their output.
Chapter 17 #2 Please answer the following about Pancreatic Control by hormones.
What are the two hormones that regulate the pancreatic secretion? And how does each regulate it?
A) Insulin and Glucagon
B) Your pancreas constantly monitors and controls your blood sugar levels using the two hormones, Insulin and Glucagon. When your blood sugar levels rise after a meal your pancreas releases insulin. Insulin allows glucose to be taken into the cells of your body where it is used for energy. It also allows glucose to be converted to glycogen which is stored in the liver and muscles. When your blood sugar levels fall below the ideal level your pancreas releases another hormone called glucagon. Glucagon makes your liver break down glycogen, converting it back into glucose which can be used by the cells for energy.