Artificial selection 5.8

?
What is artificial selection? What does it mimic?
Humans choosing and breeding only desirable characteristics in animals. This mimics natural selection - Humans determine what alleles are passed on instead of the enviroment
1 of 11
Why is artificial selection used?
To obtain organisms with the characteristics that humans require
2 of 11
Why may it take a long time?
Organisms with the required characteristics may not be developed straight away
3 of 11
What does it produce?
Organisms of the same species known as different breeds/varieties
4 of 11
What are the 2 methods of artificial selection?
Inbreeding and Outbreeding
5 of 11
What is inbreeding?
The gametes of close relative fuse
6 of 11
What is an issue of inbreeding?
Promotes homozygosity - Increases the chance of a harmful recessive gene being expressed - Known as inbreeding depression
7 of 11
How can this issue be combatted?
Introduce new genes by outbreeding
8 of 11
What is outbreeding?
Crossing unrelated varieties
9 of 11
What is the benefit of outbreeding?
Promotes heterozygosity - Introduces hybrid vigour - New sets of chromosomes are complimentary in their effects
10 of 11
Example - Milk Yield in Cattle
Select cow with highest milk yield > Select bull descended from cow with high milk yield > Cross the cow and the bull > Wait for female cows to mature and check milk yield > Select cow with highest yield > Repeat over several generations
11 of 11

Other cards in this set

Card 2

Front

Why is artificial selection used?

Back

To obtain organisms with the characteristics that humans require

Card 3

Front

Why may it take a long time?

Back

Preview of the front of card 3

Card 4

Front

What does it produce?

Back

Preview of the front of card 4

Card 5

Front

What are the 2 methods of artificial selection?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Effects of Human Activities resources »