The Digestive System

Question 1

Define Nutrition

Answer 1

Nutrition is the process by which an organism obtains and uses its food.

Question 2

Define digestion

Answer 2

Digestion is the physical and chemical breakdown of food into soluble particles that can be absorbed into the blood stream.

Question 3

What is Mechanical digestion?

Answer 3

the physical breakdown of food i.e. using teeth, churning in the stomach.

Question 4

What is chemical digestion?

Answer 4

the chemical breakdown of of food using enzymes or acids.

Question 5

Whats the need for our digestive system?

Answer 5

• Food is only processed once.
• The material needed to process the food are in a single place.
• Individual cells do not have to contain a full range of digestive enzymes.

Question 6

Whats the alimentary tube?

Answer 6

A long tube that strts at the mouth and ends at the anus.

Question 7

Stages in Human Nutrition.

Answer 7

1. Ingestion
2. Digestion
3. Absorption
4. Egestion

Question 8

Whats the name given to the process of mechanical digestion of food carried out by the teeth?

Answer 8

Mastication

Question 9

What does Saliva consist of?

Answer 9

-Water
-Salts
-Mucous
-Amylase

Question 10

Whats the Oesophagus?

Answer 10

The oesophagus is a thick, muscular walled tube that connects the pharynx to the stomach. The bolus (ball of food) travels down the oesophagus by peristalsis.

Question 11

Describe peristalsis.

Answer 11

Peristalsis is the rhythmic contraction and relaxation of the wall of the alimentary canal, causing the food to move along it.