The Digestive System

Question 1

Functions of the digestive system

Answer 1

1. To break down food into small sub-units

2. To absorb digested food into the blood or lymph

Question 2

Ingestion

Answer 2

Taking in food through the mouth

Question 3

Digestion

Answer 3

Breaking down food into small sub-units so it is small enough to be absorbed

Question 4

Absorption

Answer 4

Passing digested good through the digestive system wall into the blood or lymph

Question 5

Assimilation

Answer 5

Using absorbed food used by cells for energy, growth and defence

Question 6

Egestion

Answer 6

Removing undigested and unabsorbed food as faeces (stools) through the anus

Question 7

Excretion

Answer 7

Excretion means removing waste produced by metabolism, eg. Urea (in kidneys), carbon dioxide (in lungs).

Question 8

Two types of digestion?

Answer 8

1. Physical Digestion

2. Chemical Digestion

Question 9

Physical Digestion

Answer 9

The food is broken up into smaller pieces. It happens in the mouth, stomach and duodenum. Physical digestion increases the surface area of food. This speeds up the next step, chemical digestion.

Question 10

Chemical digestion

Answer 10

Enzymes break large molecules of food into smaller molecules. This is an example of catabolism. It also happens in the mouth, stomach and duodenum.

Question 11

Dental formula

Answer 11

I 2/2
C 1/1
PM 2/2
M 3/3

Question 12

Total number of teeth (in adult)

Answer 12

Twice the dental formula = 32

Question 13

What is saliva produced by

Answer 13

The salivary glands

Question 14

Amylase breaks down __ into __

Answer 14

Starch —> Maltose

Question 15

Optimum pH of Amylase

Answer 15

pH 8

Question 16

Optimum temperature of Amylase

Answer 16

37 °C

Question 17

Peristalsis

Answer 17

Is the movement of food among the alimentary canal by waves of muscular action (physical Digestion)