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IB Biology SL 3.2.12 HIV infection and AIDS Question Bank

Practise IB Biology SL 3.2.12 by linking HIV infection to falling lymphocytes, reduced antibodies and progressive immune-system failure.

Syllabus
First assessment 2025
Course
Biology SL
Level
SL

Exam points

  • Explain how HIV infects lymphocytes, reduces antibodies and causes immune failure leading to AIDS.
  • Use HIV data to link transmission, falling immune-cell numbers and symptoms or long-term consequences.

C3.2.12—HIV infection and AIDS question 1

[Maximum number: 1]

The graph shows changes in the relative amount of one blood component and the number of HIV RNA copies in blood plasma of an infected person over time.

Key: - Blood component

HIV RNA copies

HIV RNA copies

Figure for Question C3.2.12—HIV infection and AIDS question 1 — IB Biology SL

Which statement explains a likely symptom nine years after the initial infection?

A

The patient feels tired, as there would be fewer red blood cells to transport oxygen.

B

The patient has difficulty recovering from infectious diseases due to a lack of antibodies.

C

The risk of bleeding and blood infections increases due to a lack of clotting factors.

D

Opportunistic infections spread, as there are few phagocytes to destroy bacteria.

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