4. Digestion of foodstuffs and absorption of nutrients

Question 1

How many litres of water are absorbed from the ileum each day?

Answer 1

7-8 litres via osmosis

Question 2

How is protein digested in:

a) the stomach
b) the small intestine

Answer 2

a) Via pepsin

b) Pepsin activity terminates, trypsin and other pancreatic proteases take over

Question 3

How is fat digested in:

a) the stomach
b) the small intestine

Answer 3

a) Gastric lipase
b) Bile salts -> emulsification
Lipase activation
Formation of water soluble micelles

Question 4

What is responsible for the digestion of carbohydrates in:

a) the mouth
b) the small intestine

Answer 4

a) salivary amylase

b) pancreatic amylase, maltose, sucrase, lactase

Question 5

By what process are vitamins absorbed in the small intestine?

Answer 5

Passive diffusion

Vitamin B12 requires intrinsic factor for ileal absorption