1. Which of the following is the main function of the gastrointestinal

tract?

a) Movement of food through GI tract

b) Digestion of food by mechanical and chemical mechanisms

c) Absorption of nutrients, water, electrolytes, and vitamins

d) All of the above *

Rationale: The gastrointestinal tract performs all of these functions to

provide the body with a supply of essential substances.

2. Which of the following is a mechanical method of digestion in the

gastrointestinal tract?

a) Mastication *

b) Secretion of digestive enzymes

c) Absorption of glucose

d) Barrier and immune defense

Rationale: Mastication or chewing is a mechanical method of digestion

that breaks down food into smaller pieces and mixes it with saliva.

3. Which of the following is a chemical method of digestion in the

gastrointestinal tract?

a) Peristalsis

b) Secretion of digestive enzymes *

c) Absorption of amino acids

d) Barrier and immune defense

Rationale: Secretion of digestive enzymes is a chemical method of

digestion that breaks down food into simpler molecules that can be

absorbed.

4. Which of the following is a function of the secretory cells, glands,

intestinal epithelia, and supporting structures in the gastrointestinal tract?

a) Secretion of biological products involved in multiple digestive

processes *

b) Secretion of hormones that regulate appetite and metabolism

c) Secretion of mucus that lubricates and protects the GI mucosa

d) All of the above

Rationale: The secretory cells, glands, intestinal epithelia, and supporting