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Flashcards in 6.3 Deck (10)
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1

What is primary defence?

Pores, hair, follicles, sebaceous glands, oils—-> reduce pH, inhibit growth of bacteria

2

What is the purpose of mucous membranes?

Protect open passages

3

What happens in blood clotting?

Platelets release thrombin which causes reaction where fibrinogen becomes fibrin and produces a scab

4

What are phagocytes?

Leukocytes that engulf pathogen and contain enzymes which kill them

5

What is an antigen?

A foreign substance which triggers the production of antibodies

6

What is the function of lymphocytes

Produce antibodies specific to pathogens, which attach to antigens and signal phagocytes. Antibodies remembered in memory cells.

7

How do antibiotics kill bacteria?

Interfere with synthesis of bacterial cell wall, so the plasma membrane is exposed to excessive uptake of water and bursts.

8

What is HIV?

A tiny virus- 2 strands of RNA, enclosed in a protein coat. Retrovirus, so copies DNA of infected cells by reverse transcription

9

What are t helper cells?

Recognise antigens and trigger production of antibodies, macrophages and killer T cells

10

What does HIV do?

Destroys T helper cells, causing a loss of antibodies and thus immunity