Punnet Square Review

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

• dominant

• recessive

• homozygous

• heterozygous

In a punnet square where are the parent alleles written?

• Top and inside the boxes
• Only on the left and right side of the boxes. 
• outside of the boxes (top and left side)
• All on the top side of the boxes

Which is Heterozygous?

• Tt

• BB

• ff

• Dominant

Which is homozygeous?

• Tt

• BB

• Ff

• Blue

What are the chances that the offspring will have homozygous recessive traits?

• 1 in 4

• 3 out of 4

• 75%

• 50%

What is the dominant trait here?

• Bb

• Recessive eyes

• Blue eyes

• Brown eyes

Black hair color is dominant to white hair color in mice.  Determine the phenotypic ratio for the offpring of a heterozygous black mouse and a white mouse.

• 4 Black: 0 White
• 3 Black: 1 White
• 2 Black: 2 White
• 0 Black: 4 White

Red-green color blindness is an X-linked recessive trait. A red-green color-blind woman and a red-green color-blind man have a son. What is the probability that the son is also red-green color-blind?

• 0%
• 25%
• 50%
• 100%

T - tall and t = short
In the punnett square below, what belongs in the missing square

• tt
• Tt
• Bb
• TT

If B = brown hair and b = blonde hair, what is the probability of brown hair?

• 25%
• 50%
• 0%
• 75%