SEX LINKAGE, AUTOSOMAL LINKAGE AND EPISTASIS

Question 1

What is a sex-linked gene

Answer 1

A gene fond on a region of a sex chromosome that is not present on the other. E.g. the X chromosome.

Women are twice as likely to get the trait.

Question 2

What is EPISTASIS

Answer 2

The interaction of two genes at different loci.
One affects the expression of the other

Question 3

What is autosomal linkage

Answer 3

Two genes on the same autosome which tend to be inherited together and not assorted independently.

Question 4

What can break the liking between genes on the same chromosome
What does this result in?

Answer 4

Crossing over
Four different types of gametes rather than two

Question 5

What does it mean if most of the offspring have the parents genotypes and are expected in a 1:1 ratio

Answer 5

Linkage is complete.

Question 6

How do recombinants form
If there are more recombinants what does this mean

Answer 6

They result from crossing over which ‘recombines’ the characteristics of the original parents.
There was more crossing over

Question 7

What is F1

Answer 7

The offspring resulting from the cross between individuals with a homozygous recessive and homozygous dominant genotype

Question 8

What is F2

Answer 8

The offspring resulting from a cross between two F1 individuals