Genetics: Dominance, mutations, DNA

Question 1

What is codominance?

Answer 1

Both alleles expressed fully, produces third phenotype of offspring (e.g. roan cows)

Question 2

What is incomplete dominance?

Answer 2

Neither allele is dominant, partial expression of both traits (e.g. pink flowers)

Question 3

What is a point mutation?

Answer 3

Small scale change in DNA’s nitrogenous base sequence when cell’s genetic info is replicated accurately

Question 4

What is a base pair substitution mutation?

Answer 4

One nitrogenous base is accidentally replaced with a different one

(ACA > AGA)

Question 5

What is a insertion mutation?

Answer 5

Insertion of one or more nitrogenous bases during copying process

(ACA > ATCA)

Question 6

What is a deletion mutation?

Answer 6

Deletion of one or more nitrogenous bases during copying process

(ACA > AA)

Question 7

What is a chromosome mutation?

Answer 7

A large scale change in genetic information, an error involving entire or large part of a chromosome.

Question 8

Explain the structure of DNA.

Answer 8

Alternating backbone of pentose sugars and phosphate groups.

Nitrogenous bases connect the backbones (adenine, thymine, cytosine, guanine)

Hydrogen bonds connect the two strands