H Biology - 3.2 Animal & Plant Breeding

Which of the following is not a desirable characteristic for crops?

• Higher yields

• Pest resistance

• Disease resistance

• Intolerance to drought

Which of the following is not a desirable characteristic for livestock?

• Higher yields

• Smaller litter sizes

• Disease resistance

• Environmental tolerance

During plant field trials, what is used in order to ensure a valid comparison?

• A selection of treatments

• A number of replicates

• Randomisation of treatments

During plant field trials, what is used in order to eliminate bias?

• A selection of treatments

• A number of replicates

• Randomisation of treatments

During plant field trials, what is used to take account of variability and increase reliability?

• A selection of treatments

• A number of replicates

• Randomisation of treatments

Inbreeding involves the fusion of

• two gametes from close relatives

• two gametes from distant relatives

Inbreeding can lead to

• a loss of heterozygosity

• a lost of homozygosity

Inbreeding depression is the accumulation of

• deleterious homozygous recessive alleles

• homozygous dominant alleles

• deleterious heterozygous alleles

Why are F1 hybrids not usually bred together?

• F2 generation shows too little variation

• F2 generation shows too much variation

A test cross involves crossing an unknown genotype with an organism which is

• Unknown

• Homozygous dominant

• Homozygous recessive

• Heterozygous