KA2b Plan and Animal Breeding (cross-breeding, genetic technology)

Question 1

What is the purpose of cross breeding

Answer 1

Introduces new alleles to plant and animal lines

Question 2

What is a hybrid

Answer 2

A hybrid is an individual resulting from a cross between two genetically dissimilar parents of the same species

Question 3

Describe the effect of hybridisation

Answer 3

Breeding of two different inbred homozygous cultivars of plant species produces offspring who are uniformly heterozygous and show increased vigour, increased disease resistance and yield

Question 4

How can inbreeding be counteracted

Answer 4

Hybridisation and cross breeding

Question 5

Why are F1 hybrids not bred together

Answer 5

The F2 generation can be too genetically diverse and many will lack the improved characteristics

Question 6

how can an F1 population be maintained

Answer 6

selection and back-crossing

Question 7

state the benefit of using genome sequencing for breeding programmes

Answer 7

genetic sequencing techniques can be used to identify organisms which possess particular alleles for desired characteristics

Question 8

how can GM crop plants with improved characteristics be produced

Answer 8

single genes can be inserted into genomes using genetic transformation techniques. the transformed organism can then be used in breeding programmes

Question 9

give an example of recombinant DNA technology in plants

Answer 9

genes for vitamin A was inserted into normal rice to produce golden rice - a rice plant providing better nutrients for consumers in developing countries where Vitamin A deficiencies are common