Topic 2: Plant and Animal breeding Flashcards
Why does plant and animal breeding take place?
To improve characteristics to help support sustainable food production
Breeders develop crops and animals with what properties?
Higher food yields,
higher nutritional values,
resistance to pests and diseases,
that thrive in particular environmental conditions
What are the purpose of field trials?
To compare performance of different cultivars or treatments,
to evaluate GM crops
Which factors have to be taken into account when designing a field trial?
Selection of treatments,
the number of replicates,
the randomisation of treatments
The selection of treatments for field trials must be done in a way to ensure what?
The selection of treatments for field trials must be done in a way that ensures VALID COMPARISONS
The number of replicates must take account of the _______ within the sample?
Variability
What must the randomisation of treatments due when measuring treatment effects?
Eliminate bias
What is the definition of inbreeding?
In inbreeding, selected related plants or animals are bred for several generations until the population breeds due to the desired type
In inbreeding, what is eliminated?
The population breeds true because inbreeding eliminates heterozygotes
What does inbreeding cause?
Inbreeding causes an increase in the frequency of individuals who are homozygous for the recessive, deleterious alleles
What happens to the individuals with recessive, deleterious alleles?
Will do less well at surviving to reproduce
How does inbreeding depression arise?
From the increased frequency and homozygous, recessive deleterious alleles
Why are self pollinating plants less susceptible to inbreeding depression?
They are naturally inbreeding and less susceptible to inbreeding depression due to the elimination of deleterious alleles by natural selection
How current patterns of inheritance in inbreeding be analysed?
Using monohybrid crosses
Animals from different breeds may produce what?
A new crossbreed population
A new cross breed population may have what?
Improve characteristics
How can you alleles be introduced into a plant or animal lines?
By crossing a cultivar or breed with an individual with a different, desired genotype
Implants, how are F1 hybrids produced?
Crossing two different inbred lines to create a relatively uniform heterozygous crop
What is the benefit of F1 hybrids?
Increased vigour and yields
In inbreeding why are animals and plants usually not bred together in F1?
Because the F2 produced shows too much variation
What can happen as a result of genome sequencing?
Organisms with desirable genes can be identified and then used in breeding programs
Breeding programs can involve crop plants with what properties?
Can involve crop plants that have been genetically modified using recombinant DNA technology
In genetic technology what happens to the single genes that have the desirable characteristics?
Single gene is for desirable characteristics are inserted into the GM crop plants, to create GM plants with improved characteristics
What are some examples of recombinant DNA technology in plant breeding?
- Insertion of BT toxin gene into plants for pest resistance,
- Glyphosate resistant gene inserted for herbicide tolerance