The small intestine

Question 1

how long is the small intestine

Answer 1

6 meters

Question 2

what is the longest part of the alimentary canal

Answer 2

the small intestine

Question 3

what does the small intestine consist of

Answer 3

• duodenum
• jejunum
• ileum

Question 4

what is the start of the small intestine

Answer 4

duodenum

Question 5

what is the middle part of the small intestine

Answer 5

jejunum

Question 6

what is the end part of the small intestine

Answer 6

ileum

Question 7

what percentage of nutrients are absorbed here

Answer 7

90%

Question 8

how can a large surface area be achieved to absorb the products of digestion

Answer 8

The mucosa has folds that extend into the interior. Small finger-like projections called villi to extend from the folded surface. Cells covering the villi have microscopic projections called microvilli.

Question 9

where do digestive enzymes enter from

Answer 9

• liver (bile duct)
• pancreas (pancreatic duct)
• mucosa of the intestine (gland cells)

Question 10

how are glucose and amino acid absorbed into villi

Answer 10

Glucose and amino acid are absorbed into the blood capillaries of villi through active transport, due to the high concentration of amino acids and glucose in the capillary.

Question 11

how are vitamins and minerals absorbed into villi

Answer 11

vitamins and minerals are absorbed into the blood capillaries of villi through simple diffusion as there is a higher concentration of nutrient materials in the interior of the small intestine than in the cells lining the villi.

Question 12

how are fatty acids and glycerol absorbed into villi

Answer 12

Fatty acids and glycerol are absorbed by simple diffusion. In the cells on the villi, the fatty acids and glycerol recombine to form fats. The tiny fat droplets that enter the lacteal are taken by the lymphatic system