DAT DAT - Dental Admission Biology: Genetics and Heredity 2

Question 1

In a testcross, an organism of unknown genotype is crossed with which individual?

Accepted Answer

A homozygous recessive individual

Answer

A heterozygote

Answer

A homozygous dominant individual

Answer

A sibling

Question 2

For an X-linked recessive trait, which parent passes the allele to an affected son?

Accepted Answer

Mother only

Answer

Father only

Answer

Either parent equally

Answer

Neither parent

Question 3

A standard dihybrid cross (AaBb × AaBb) produces which classic phenotypic ratio?

Accepted Answer

9:3:3:1

Answer

1:2:1

Answer

3:1

Answer

1:1:1:1

Question 4

Genes that are physically located on the same chromosome are described as:

Accepted Answer

Linked

Answer

Pleiotropic

Answer

Codominant

Answer

Epistatic

Question 5

The recombination frequency between two genes is used to estimate:

Accepted Answer

The physical distance between genes on a chromosome

Answer

Gene expression levels

Answer

The number of alleles present

Answer

The mutation rate

Question 6

Human skin color is determined by multiple genes contributing to a continuous range of phenotypes — this is an example of:

Accepted Answer

Polygenic inheritance

Answer

Pleiotropy

Answer

Codominance

Answer

Epistasis