Mutations and antibiotic resistance

Question 1

What are mutations?

Answer 1

Rare, random changes in an organism’s DNA that can be inherited.

Question 2

How do mutations work?

Answer 2

They change the sequence of the DNA bases in a gene, which produces a genetic variant.

Question 3

What can mutations lead to?

Answer 3

A different phenotype, increasing variation

Question 4

What effect do most mutations have on the phenotype?

Answer 4

None

Question 5

What effect will some mutations have on the phenotype?

Answer 5

A small one

Question 6

What effect will very few mutations have on the phenotype?

Answer 6

A significant one

Question 7

What physical factors increase the chances of mutations?

Answer 7

Ionizing radiation e.g. gamma rays and chemicals (called mutagens) e.g. chemicals in tobacco

Question 8

How can bacteria evolve and become antibiotic resistant?

Answer 8

1) They are variable to mutations.
2) This can mean that a mutated bacterium is less affected by a particular antibiotic.
3) This will survive in the host and reproduce to create offspring with the same allele for this characteristic.
4) This is effectively natural selection.
5) This process repeats itself to form a disease-resistant population of bacteria.

Question 9

What are ‘superbugs’?

Answer 9

Bugs that are resistant to the most common antibiotics e.g. MRSA