B17 variation and selection Flashcards
1
Q
describe what is meant by variation
A
- differences between individuals
- of the same species
2
Q
what does continuous variation result in
A
- range of phenotypes between 2 extremes
- eg body length
3
Q
what does discontinuous variation result in
A
- limited number of phenotypes with no intermediates
- eg ABO blood groups
4
Q
describe what is meant by mutation
A
- a genetic change
- the way in which new alleles are formed
5
Q
describe natural selection
A
- genetic variation within populations
- production of many offspring
- struggle for survival, including competition for resources
- individuals better adapted to environment more likely to reproduce
- pass alleles to next generation
6
Q
describe selective breeding
A
- selection by humans of individuals with desirable features
- cross them to produce next generation
- selection of offspring showing desirable features
7
Q
what is the development of strains of antibiotic-resistant bacteria an example of
A
natural selection
8
Q
how does selective breeding by artificial selection benefit us
A
- improve crop plants
- improve domesticated animals
