B13 - Variation and evolution Flashcards
1
Q
What is variation?
A
Differences in the characteristics of individuals in a population
2
Q
What causes variation?
A
Differences in the genes inherited and conditions (environmental causes)
3
Q
What can affect human development?
A
If the mother smokes or drinks while pregnant, the baby may have a low birth rate and other problems
4
Q
How can plants development be affected?
A
Lack of light, nutrients and space to grow
5
Q
What does a mutation lead to?
A
A new phenotype
6
Q
What is selective breeding?
A
Humans breed animals and plants to get desired characteristics
7
Q
Examples of desired characteristics?
A
- Disease resistance
- Domestic dogs with a gentle nature
8
Q
Limitations of selective breeding?
A
- Reduces number of alleles in population
- Less variation between individuals and population
- New disease or climate change could destroy whole of population
