Practice A2.3 Viruses (HL) with authentic IB Biology exam questions for both SL and HL students. This question bank mirrors Paper 1A, 1B, 2 structure, covering key topics like cell biology, genetics, and ecology. Get instant solutions, detailed explanations, and build exam confidence with questions in the style of IB examiners.
Paper
Level
Question 1
HLPaper 1A
The graph shows the concentrations (log10 particles/ml) of E. coli host cells (blue line) and phage particles (red line) over time during bacteriophaqe lambda infection.
Based on the trends shown, which conclusion is most strongly supported?
Question 2
HLPaper 1A
Which feature distinguishes the influenza virus shown in the image from bacteriophage lambda?
Question 3
HLPaper 1A
The diagram shows the life cycle of a virus. Which step involves the virus entering the host cell?
Question 4
HLPaper 1A
The diagram shows a virus infecting an animal cell.What is the first step in viral infection?
Question 5
HLPaper 2
1.[7]
Explain how reverse transcriptase allows retroviruses to replicate within a host cell.
Question 6
HLPaper 1A
What is the function of the viral RNA?
Question 7
HLPaper 1B
The following electron microscope image shows the structure of a virus:
Additionally, the table below compares key characteristics of viruses and living cells:
| Feature | Virus | Living Cell |
|---|---|---|
| DNA or RNA | Yes | Yes |
| Metabolism | No | Yes |
| Ability to Reproduce | Only inside host cell | Yes (independent cell division) |
| Ribosomes | No | Yes |
| Response to Antibiotics | No | Yes (for bacteria) |
1.[2]
Based on the image and data, explain why viruses are considered non-living organisms.
2.[2]
Describe one method by which viruses reproduce inside a host cell.
Question 8
HLPaper 2
1.[7]
Focusing on the effects on the host cell and the timing of viral replication, compare and contrast the lytic and lysogenic life cycles of viruses.
Question 9
HLPaper 2
1.[7]
Explain how the envelope helps viruses evade the host immune system and enhance their infectivity.
Question 10
HLPaper 2
Discuss the impact of viruses on global health, providing examples of major viral pandemics and the strategies used to control viral outbreaks.
1.[4]
Outline the impact of viruses on global health.
2.[4]
Describe the key characteristics of a major viral pandemic, including its impact on global health and at least one strategy used for its control.
3.[7]
Discuss the strategies used to control viral outbreaks.