Digestive System 3

Question 1

What are the 3 phases of secretion in the stomach ?

Answer 1

1. Cephalic
2. Gastric
3. Intestinal

Question 2

What is the cause of the cephalic phase ?

Answer 2

Sensations and thoughts

Question 3

What is the effect of the cephalic phase ?

Answer 3

Cerebral cortex/ hypothalamus
Parasympathetic- vagus

Question 4

What do enteroendorcine cells in the small intestine release ?

Answer 4

1. Cholecystokinin (CCK)
2. Gastric inhibitory peptide (GIP)
3. Secretin
   They inhibit gastric secretion.

Question 5

What effect do CCK and secretin have on the pancreas?

Answer 5

CCK stimulates secretion of pancreatic juice rich in bicarbonate ions
Secretin stimulates secretion of pancreatic juice rich in digestive enzymes

Question 6

What effect do CCK and secretin have on the liver ?

Answer 6

CCK causes contraction of the gallbladder.
Secretin enhances flow of bile rich in bicarbonate ions from the liver

Question 7

What are satiety signals ?

Answer 7

They make you feel like you don’t want to eat anymore. You are full.

Question 8

What is CCK ?

Answer 8

It is secreted in response to food.
Reduces appetite and inhibits eating

Question 9

Name 5 satiety signals

Answer 9

1. Glucagon-like peptide-1, from intestine
2. Peptide YY, from intestine
3. Leptin, from white adipose tissue
4. Insulin
5. Oestrogen

Question 10

What is ghrelin ?

Answer 10

A hormone that increases food intake, it is a hunger signal

Question 11

Where is ghrelin secreted from ?

Answer 11

Endocrine cells of gastric mucosa