Q BankQuestion BankDocsDocuments

C3.2.12—HIV infection and AIDS

HIV infection and AIDS explains how a specific barrier, pathogen interaction, immune mechanism or treatment response contributes to protection against infectious disease.

Syllabus
First assessment 2025
Objective
C3.2.12
Level
HL

Exam analysis

Chance of appearing3%of analysed past papers
Latest appearanceNovember 2025
Most common paperPaper1
Typical marks1–4

Common command terms

  • Identify
  • Explain
  • Discuss

Scoring notes

Common mistake
Confusing plasma cells, memory cells and helper T-cells in the activation sequence.

Recent exam appearances

November 2025Paper2 ["HL"] · TZ18(c)[ 4 ]C3.2.12—HIV infection and AIDS
November 2019Paper1 ["HL"] · TZ022[ 1 ]C3.2.12—HIV infection and AIDS
May 2012Paper1 ["HL"] · TZ221[ 1 ]C3.2.12—HIV infection and AIDS
Practice this objective

Coverage 2012–2025 · Updated 16 Jul 2026

Concept essentials

  • HIV infection and AIDS has to be linked to the exact pathogen, cell, molecule or population process involved.
  • The biological effect of hiv infection and aids depends on the sequence from trigger to protective outcome.
  • Clear distinctions within hiv infection and aids prevent confusion with neighbouring immune responses.
  • Evidence for hiv infection and aids is strongest when mechanism and consequence are explained together.
ConceptIB Biology HL