3.2 Criteria

Question 1

Breeders develop crops and animals with what? (4)

Answer 1

1. higher food yields
2. Higher nutritional values
3. Resistance to pests and diseases
4. Ability to thrive in particular environmental conditions

Question 2

Define a cultivar (cultivated variety):

Answer 2

A plant created or selected fro desirable characteristics and can be maintained by cultivation

Question 3

Plant field trials compare the performance of different what? (3)

Answer 3

1. cultivars
2. treatments
3. GM crops

Question 4

Plant field trials must what? (3)

Answer 4

1. Select treatments to ensure valid comparisons
2. Use sufficient replicates to take account of variability within the sample
3. Randomise treatments to eliminate bias

Question 5

Explain the process of inbreeding:

Answer 5

Selecting related plants or animals, and breeding them for several generations until the population breeds true to the desired type due to the elimination of heterozygotes

Question 6

Inbreeding may result in what?

Answer 6

Inbreeding depressions

Question 7

What is meant by inbreeding depression?

Answer 7

Where there is an increase in the frequency of individuals who are homozygous for recessive deleterious alleles.

Question 8

Individuals showing inbreeding depressions are less likely to survive to reproduce due to what? (5)

Answer 8

1. reduced vigour
2. poor health
3. reduced size
4. low disease resistance
5. may show reduced yeild

Question 9

Cross breeding introduces new alleles to plant and animal lines by crossing what?

Answer 9

Crossing a cultivar or breed with an individual showing a different desired phenotype

Question 10

In animals, the new cross breed population shows improved what?

Answer 10

Characteristics

Question 11

The two parental lines used to produce the improved crossbreeds are maintained to allow what?

Answer 11

Continued production of crossbreeds

Question 12

In some plants two different inbred lines are crossed to produce F1 hybrids which show?

Answer 12

A uniform hetrozygous crop

Question 13

F1 hybrids show increased what?(4)

Answer 13

1. Increased vigour
2. increased disease resistance
3. increased growth rates
4. increased yield

Question 14

Genomic sequencing allows individuals carrying desirable to be what?

Answer 14

Identified and then used in breeding programmes

Question 15

GM crop plants with improved characteristics can be produced by doing what?

Answer 15

Inserting single genes for desirable characteristics into their genomes

Question 16

GM crops can also produced by using what?

Answer 16

Recombinant DNA technology

Question 17

Name 2 examples of recombinant DNA technology in plants:

Answer 17

1. Insertion of Bt toxin gene for past resistance
2. Insertion of glyphosate resistance gene for the herbicide tolerance