8: How does a purebred individual differ from a hybrid individual?

9: How could two black cats produce and albino kitten? Use a diagram to explain your answer.

10: If you wanted to be certain that a trait would appear in the offspring of the plants or animals that you were breeding, what would you have to find out about the parents?

8. Purebreds are the result of mating between genetically similar parent and hybrid are the offsprings produced from genetically dissimilar parents.

9. Mating of two heterozygous black cats.

10. The genotype of the parents must be known.

Explanation:

8. Pure bred individual resulting from homozygous parents for either dominant or recessive traits. Hybrid individuals are those organisms that are produced by heterozygous parents.

Example RR X rr

Rr Rr Rr Rr    pure bred

Rr X Rr

RR Rr RR Rr

1:1 is the ratio of hybrid individual produced.

Pure breds are the result of mating between genetically similar parent and hybrid are the offsprings produced from geneticaly dissimilar parents.

9. The two black cats must be heterozygous as Bb and Bb as black is the dominant colouir of fur in cats. The heterozygosity explains that recessive trait b for white is present in the parent black cats.

from the punnet square;

   P    p

P  PP  Pp

p  Pp  pp

There are 25% chances of white or albino cat 25%.

10. The punnet square is used to study the prediction of traits appearing in the organism.

For the traits to appear in next generation the genotype of the parent must be known in order to predict the percentage appearance of  phenotypic trait in the individual plant or animal.

Selective breeding is based on this assumption only.