Infectious diseases: AS Level Biology questions with answers
Free Infectious diseases questions for AS Level Biology (9700), part of Transport & disease. Each question has the answer and the marking points an examiner would look for.
Which row matches the disease with its pathogen and transmission?
tuberculosis
malaria
cholera
A
bacterium; airborne droplets
protoctist; contaminated water
virus; contaminated water
B
bacterium; airborne droplets
virus; Anopheles mosquito
bacterium; contaminated water
C
bacterium; airborne droplets
protoctist; Anopheles mosquito
bacterium; contaminated water
D
virus; airborne droplets
protoctist; Anopheles mosquito
bacterium; contaminated water
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Answer: C
Question 2Multiple choice · 1 mark
Which term is described by this statement? “Bacteria surviving an antibiotic that would normally kill them.”
A negative feedback
B resolution
C antibiotic resistance
D endemic disease
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Answer: C
Question 3Multiple choice · 1 markA* challenge
Penicillin is used to treat bacterial infections. 1 Penicillin has no effect on viruses because they have no cell wall. 2 Penicillin damages human cell walls. 3 Penicillin works best on bacteria that are growing. Which statements are correct?
A 1, 2 and 3
B 1 and 3 only
C 1 only
D 3 only
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Answer: B
Question 4Multiple choice · 1 markA* challenge
Which row describes HIV?
type of nucleic acid
enzyme it carries
main cells infected
A
RNA
reverse transcriptase
B-lymphocytes
B
RNA
reverse transcriptase
T-helper lymphocytes
C
RNA
DNA polymerase
T-helper lymphocytes
D
DNA
reverse transcriptase
T-helper lymphocytes
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Answer: B
Question 5Structured · 3 marksA* challenge
Antibiotic resistance is increasing.
Explain how bacteria become resistant to an antibiotic.
[3]
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Part
Answer and marking points
Marks
mutation; selection pressure; resistant survive and reproduce
random mutation gives resistance B1 antibiotic kills susceptible bacteria (selection pressure) B1 resistant bacteria survive, reproduce and pass on the allele B1
3
Question 6Structured · 4 marks
Tuberculosis and malaria are infectious diseases.
(a)
Name the pathogen that causes TB and describe how it is transmitted.
[2]
(b)
Describe how malaria is transmitted.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
Mycobacterium tuberculosis; droplets
Mycobacterium tuberculosis (or M. bovis) B1 airborne droplets from coughing/sneezing B1
2
(b)
Plasmodium; Anopheles mosquito vector
Plasmodium (protoctist) B1 transmitted by female Anopheles mosquito when it takes a blood meal B1
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in