B14.3 Selective Breeding

Question 1

What is selective breeding ?

Answer 1

Breeding individuals with desired traits to produce offspring/ generations that also express the trait

Question 2

What are the advantages of selective breeding ?

Answer 2

A cheap, natural way to replicate/ increase a desired trait within a population

Question 3

What have domestic dogs been bred for ?

Answer 3

Have a gentle nature

Question 4

What have food crops been selectively bred for ?

Answer 4

Disease resistance
Eg wheat

Question 5

What have cows been selectively bred for ?

Answer 5

To produce more meat or milk

Question 6

What jab plants been selectively bred for ?

Answer 6

Larger flowers
To smell nice

Question 7

What are the disadvantages of selective breeding ?

Answer 7

Inbreeding
- increased risk of inherited disorders
Reduced variation
- susceptible to change eg a new disease
Not all of the offspring are desired/ wanted

Question 8

Describe the stages of selective breeding ?

Answer 8

Parents with desired trait(s) are bred

Offspring with desired trait(s) are selected

Repeated over several generations until the desired result is achieved

Question 9

If a farmer wanted to selectively breed cows that produce the most milk what would he do ?

Answer 9

First he would find the female cow that produces the most milk, he would then breed this cow
The offspring that produced the most milk would then breed and reproduce offspring
This cycle will be repeated until the farmer is satisfied with the yield of milk