TOPIC 7: VARIATION

Question 1

Evolution (definition)

Answer 1

a change in the inherited characteristics of a population over time through a process of natural selection which may result in the formation of new species

Question 2

Natural Selection

Answer 2

1) organisms produce more offspring than the environment is able to support
2) it creates competition for resources which results in a ‘struggle for survival’ 3) Individuals with characteristics most suited to the environment have a higher chance of survival and more chances to reproduce
4) the alleles resulting in these characteristics are passed to their offspring at a higher rate than those with characteristics less suited to survival
5) Meaning that in the next generation, there will be a greater number of individuals with the better adapted variations in characteristics

Question 3

Antibiotic Resistance

Answer 3

some bacteria start to develop resistance to antibiotics → they reproduce → more bacteria are resistant to antibiotics → antibiotics are ineffective

Question 4

Sources of Variation

Answer 4

environment & gene (fertilisation)