Infectious diseases
Cambridge A-Level Biology (9700) · Unit 10: Infectious disease · 11 flashcards
Infectious diseases is topic 10.1 in the Cambridge A-Level Biology (9700) syllabus , positioned in Unit 10 — Infectious disease , alongside Antibiotics. In one line: Cholera is caused by a bacterium called Vibrio cholerae.
Marked as AS Level: examined at AS Level in Paper 1 (Multiple Choice), Paper 2 (AS Structured Questions) and Paper 3 (Advanced Practical Skills). The same content may also be assumed in Paper 4 (A Level Structured Questions).
The deck below contains 11 flashcards — 4 definitions and 7 key concepts — covering the precise wording mark schemes reward. Use the 4 definition cards to lock down command-word answers (define, state), then move on to the concept and calculation cards to handle explain, describe, calculate and compare questions.
What type of pathogen causes cholera, and what is its name
Cholera is caused by a bacterium called Vibrio cholerae.
What the Cambridge 9700 syllabus says
Official 2025-2027 spec · AS LevelThese are the exact learning outcomes Cambridge sets for this topic. The candidate is expected to be able to do each of these on the relevant paper.
- state that infectious diseases are caused by pathogens and are transmissible
- state the name and type of pathogen that causes each of the following diseases: • cholera – caused by the bacterium Vibrio cholerae • malaria – caused by the protoctists Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale and Plasmodium vivax • tuberculosis (TB) – caused by the bacteria Mycobacterium tuberculosis and Mycobacterium bovis • HIV/AIDS – caused by the human immunodeficiency virus (HIV)
- explain how cholera, malaria, TB and HIV are transmitted
- discuss the biological, social and economic factors that need to be considered in the prevention and control of cholera, malaria, TB and HIV (details of the life cycle of the malarial parasite are not expected)
Cambridge syllabus keywords to use in your answers
These are the official Cambridge 9700 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.
Tips to avoid common mistakes in Infectious diseases
- › State clearly that virus particles have a genome of either DNA or RNA and a protective protein coat called a capsid.
- › Use provided information; if told an antibiotic binds to ribosomes, explain its effect on protein synthesis (translation), not cell walls.
- › Ensure you distinguish between 'immunity' (an organism’s defense) and 'resistance' (a pathogen's ability to withstand antibiotics).
- › Use 'contaminated' for abiotic vectors like water/food and 'infected' for living organisms like the human host.
- › Antibiotics target bacteria, not human cells; therefore, only the bacteria can be resistant. Humans develop immunity to pathogens.
What type of pathogen causes cholera, and what is its name?
Cholera is caused by a bacterium called Vibrio cholerae.
Name four types of pathogens that cause malaria.
Malaria is caused by the protoctists Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale and Plasmodium vivax.
What are the names of the two bacteria that cause tuberculosis (TB)?
Tuberculosis (TB) is caused by the bacteria Mycobacterium tuberculosis and Mycobacterium bovis.
What type of pathogen causes HIV/AIDS, and what is its name?
HIV/AIDS is caused by a virus called the human immunodeficiency virus (HIV).
Describe the transmission route of cholera.
Cholera is typically transmitted through the ingestion of food or water contaminated with the feces of an infected person. Poor sanitation and hygiene are major contributing factors.
Explain how malaria is transmitted.
Malaria is transmitted to humans through the bite of infected female Anopheles mosquitoes. These mosquitoes carry Plasmodium parasites, which are injected into the human bloodstream during the bite.
Describe the common transmission routes of Tuberculosis (TB).
TB is primarily transmitted through the air when a person with active TB coughs, sneezes, speaks, or sings, releasing infectious droplets containing the bacteria. Prolonged close contact is usually required for transmission.
Explain how HIV is transmitted.
HIV is transmitted through direct contact with certain bodily fluids (blood, semen, vaginal fluids, breast milk) from an infected person. Common routes include unprotected sexual intercourse, sharing needles, and from mother to child during pregnancy, childbirth, or breastfeeding.
Discuss one biological factor to consider in the prevention and control of malaria.
A biological factor to consider is the development of insecticide resistance in mosquitoes, which reduces the effectiveness of mosquito control programs. New insecticides or alternative control methods may be needed.
Describe a social factor that contributes to the spread of tuberculosis (TB).
Poverty and overcrowding are significant social factors. Poor living conditions increase the risk of TB transmission due to close proximity and weakened immune systems in malnourished individuals.
Explain an economic impact of HIV/AIDS on a community.
HIV/AIDS can significantly reduce the workforce, leading to decreased productivity and economic output. Healthcare costs associated with treating HIV/AIDS patients also strain economic resources.
More topics in Unit 10 — Infectious disease
Infectious diseases sits alongside these A-Level Biology decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.
Key terms covered in this Infectious diseases deck
Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.
How to study this Infectious diseases deck
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