Mod. 7 Inq. 3

Question 1

What is immunity?

Answer 1

The ability of the body to resist disease. It can be gained naturally or artificially and is either passive or active.

Question 2

Innate Immunity

Answer 2

• present at birth and is genetically determined
• non-specific
• physical and chemical barriers and cellular responses

Question 3

Adaptive Immunity

Answer 3

• specific defence mechanism consisting of cells targeted at specific pathogens
• acquired
• third line of defence

Question 4

First Line of Defence - chemical barriers

Answer 4

• acid in the stomach
• alkali in the small intestine
• lysosome enzyme in tears

Question 5

First Line of Defence - physical barriers

Answer 5

• skin
• mucous membranes
• cilia lining air passages
• microflora
• body secretions (saliva, urine, sweat)

Question 6

Outline phagocytosis

Answer 6

2nd line of defence
Non-specific process where white blood cells (phagocytes) attack foreign substances and engulf and destroy them.

Question 7

Outline inflammation

Answer 7

2nd line of defence
Release of histamine dilates the blood vessels, increases their permeability and releases chemicals which attract phagocytes. This causes increased fluid leaving the blood vessel.

Question 8

Role of the lymphatic system

Answer 8

System of vessels and lymph nodes that return fluid to the blood. It is important in controlling tissue fluid balance, lipid transport and defence against disease.

Question 9

Define antigen

Answer 9

A term for a substance that triggers the immune response.

Question 10

Third Line of Defence