Nutrition: Digestion

Question 1

What 3 parts make up the human small intestine?

Answer 1

1. Duodenum
2. Jejunum
3. Ileum

Question 2

The MUCOSA of the small intestine is folded and its surface is made up of numerous finger-like projections.

(a) What is the name given to these projections?
(b) How long are they?

Answer 2

(a) villi

(b) approx 0.5-1.5mm

Question 3

What are the villi covered by?

Answer 3

Mature cells and occasionally mucus secreting goblet cells.

Question 4

What are these mature cells (that coat the villi) called?

and what type of cell are they?

Answer 4

They’re called enterocytes and they are columnal epithelial cells

Question 5

What are present on the luminal surface of each of the enterocytes?

Answer 5

Thousands of microvilli.

Question 6

What are the enterocytes responsible for?

Answer 6

Absorption and some digestion.

Question 7

What is the purpose of the structural features of the small intestine?

Answer 7

the structural features help to increase the surface area for absorption of nutrients