inheritance and evolution

Question 1

What do results from a genetic cross of 2 different phenotypes showing same/similar numbers of offspring for the 2 phenotypes show?

Answer 1

1. The two genes are linked
2. No crossing over

Question 2

In genetic crosses, the observed phenotypic ratios obtained in the offspring are often not the same as the expected ratios, suggest 2 reasons why

Answer 2

1. Fertilisation of gametes is random
2. Epistasis

Question 3

What is meant by the term phenotype?

Answer 3

1. Expression of genetic constitution of alleles
2. Characteristics due to the environment

Question 4

What is meant by codominant alleles?

Answer 4

1. Both alleles expressed in the phenotype

Question 5

In fruit flies, the genes for body colour and wing length are linked. Explain what this means

Answer 5

1. Genes are on the same chromosome