[SEC 3] CHAPTER 5 - Nutrition In Humans

Question 1

What is the outer muscle of the oesophagus?

Answer 1

Longitudinal muscles

Question 2

What is the inner muscle of the oesophagus?

Answer 2

Circular muscles

Question 3

Define peristalsis

Answer 3

Peristalsis is the rhythmic, wave-like muscular contractions in the wall of the alimentary canal

Question 4

What is the function of peristalsis

Answer 4

Peristalsis enables food to be mixed with digestive juices, and also pushes or propels the food along the alimentary canal

Question 5

What happens when the circular muscles contract?

Answer 5

When the circular muscles contract, the longitudinal muscles relax. As a result, the wall of the alimentary canal constricts, that is, the alimentary canal becomes narrower and longer. The food is squeezed or pushed forward

Question 6

What happens when the longitudinal muscles contract?

Answer 6

When the longitudinal muscles contract, the circular muscles relax. The alimentary canal dilates, that is, it becomes wider and shorter. This widens the lumen for food to enter

Question 7

What is the inner surface of the stomach lined with and what is its function?

Answer 7

Name: Gastric glands
Function: secrete gastric juice

Question 8

What is the first part of the small intestine?

Answer 8

Duodenum

Question 9

What do liver cells produce and secrete, and what is its appearance and function?

Answer 9

Name: bile

Appearance: alkaline greenish-yellow liquid containing blue salts

Function: emulsify fats into tiny fat droplets

Question 10

Define assimilation

Answer 10

Conversion of absorbed food molecules into new protoplasm or used to provide energy