2nd Line Of Defence

Question 1

Fever

Answer 1

Is an abnormally high body temperature which is triggered by the release of prostaglandins.
- Helps to combat infection by reducing the growth rate of pathogens.

Question 2

Inflammation

Answer 2

The inflammatory response is the way in which the body reacts when pathogens damage cells
- When tissue damage occurs, mast cells release a chemical called histamine, which causes the capillaries to dilate

Question 3

Cellular responses

Answer 3

• Phagocytes

- Natural killer

Question 4

Phagocytes

Answer 4

Phagocytes engulf and digest foreign material and debris as well as wound healing and inflammation.
- Have receptors on surface and are chemically attracted to the region of infection by products of cytokines, microorganisms and damaged cells.

Question 5

Natural killer cells

Answer 5

A lymphocyte able to bind to certain tumour cells and virus-infected cells without the stimulation of antigens, and kill them by the insertion of granules containing perforin.
- Initiated by interferons and can detect cancerous and virus infected cells by changes in the surface of body cells

Question 6

Antigen presenting cells

Answer 6

• Macrophages
• Dendritic cells
• B cells
• Phagocytes

Question 7

Phagocytosis, seven steps

Answer 7

1. Chemotaxis and adherence of microbe to phagocyte
2. Ingestion of microbe by phagocyte
3. Formation of phagosome
4. Fusion of phagosome with lysosome to form phagolysosome
5. Digestion of ingested microbe by enzymes
6. Formation of residual body containing indigestible material
7. Release of waste materials

Question 8

Chemical responses

Answer 8

• Fever

- Inflammation