Peerwise Deck

Question 1

How to work out number of sperm + egg?

Answer 1

2^number of heterozygous loci

Question 2

What is the number of F2 genotypes?

Answer 2

3^number of heterozygous loci

Question 3

A test cross is used to…

Answer 3

Determine whether an individual expressing the dominant phenotype is homozygous or heterozygous

Question 4

Work out gene order in a trihybrid cross

Answer 4

Look at 2 double recombinants and gene that’s changed is the one in the middle

Question 5

To determine map distance

Answer 5

1. Deal with each loci in pairs
2. Identify recombinant classes
3. Distance between two loci = Number of recombinants between 2 loci / total number of offspring X 100

Question 6

In genetic linkage :

Answer 6

A deficiency of recombinant genotypes in the gametes

Question 7

Acrocentric

Answer 7

Off-Centre centromere

Question 8

If autosomal linkage

Answer 8

Only through female lineage

Question 9

Coat colour in the mouse serves as a good example of

Answer 9

Epistasis

Question 10

Y-linked

Answer 10

Genes located on the Y-chromosome and appearing only in males

Question 11

Sex limitation

Answer 11

The same allele has different expressions in male and female individuals.

Question 12

Achondroplasia is an

Answer 12

Autosomal dominant disease

Question 13

Atavism

Answer 13

Phenotypic traits disappearing and then reappearing later in the phylogenetic tree.

Question 14

Equation to work out probability in more than 1 scenario

Answer 14

P(k out of n) = n! / (k!(n-k)! x p^k x q^(n-k)

• > where p = probability of occurrence and q= probability of non-occurence
• k = number of times outcome p occurs