Genetics Check

In a Punnett square, a lower case letter stands for a ____________ allele.

• dominant

• recessive

• homozygous

• heterozygous

Hair color, height, eye color and freckles are examples of human traits. What do we call the physical expression of the genetic material of an organism?

• genetics

• heredity

• genotype

• phenotype

Heterozygous is when...

• the alleles are the same.

• the alleles are different.

• the alleles are absent.

• the alleles are present.

T = tall and t = short

In the punnett square shown, what belongs in the missing square

• tt

• Tt

• Bb

• TT

In a heterozygous genotype, the ___________ allele takes over in the phenotype.

• recessive

• dominant

G = green, g = yellow
The genotype for a yellow plant is...

• GG
• Gg
• gg
• all of the choices result in yellow

In plants, tall (T) is dominant to short (t). Perform the following cross: Tt x Tt. What is the probability of producing a short plant?

• 0%

• 25%

• 50%

• 75%

What ratio of the offspring from the cross shown will be homozygous recessive for the trait of tallness? 

• 0 in 4
• 1 in 4
• 2 in 4
• 4 in 4

A black guinea pig (BB) and a white guinea pig (bb) mate. What is the chance that a white guinea pig will be born?

• 0%

• 25%

• 50%

• 75%

• 100%

Which of the following genotypes is heterozygous?

• Bb

• BB

• bb

• B