Bacteria, antibiotics and resistance

≈ 48 min

Bacteria, antibiotics and resistance

Bacteria are living single cells with metabolism, ribosomes and DNA. Antibiotics can disrupt bacterial cell walls, protein synthesis or other bacterial processes. In a bacterial population, genetic variation may mean a few cells survive a particular antibiotic. Those survivors reproduce, so the resistant trait becomes more common. The antibiotic does not deliberately create resistance; it selects among variation already present or produced by mutation.

Work it through

Imagine one million bacteria, including ten with a resistance gene. An antibiotic kills most susceptible bacteria. The ten resistant cells remain and reproduce. The next population contains a much higher proportion of resistant bacteria.

Mastery target

Explain resistance as selection across a population, using variation, survival and reproduction.

What changes first when an antibiotic is used on a mixed bacterial population?

Susceptible bacteria are more likely to die than resistant bacteria.

Every bacterium decides to become resistant.

Viruses become bacteria.

Human cells gain bacterial cell walls.

Name the key biological term from Bacteria, antibiotics and resistance: enter the term that best fits the explanation and visual model.

Which practice best slows antibiotic resistance?

Use antibiotics only when prescribed and complete the prescribed course.

Use leftover antibiotics for any cold.

Share antibiotics with friends.

Stop once symptoms improve.

Which statement corrects a common misunderstanding in Bacteria, antibiotics and resistance?

Correct: Stopping an antibiotic course early can leave the most tolerant bacteria alive; feeling better does not prove the infection is gone.

A single observation is enough to prove every biological claim.

Scientific terms are interchangeable whenever they sound similar.

A process always has exactly the same result in every environment.