Adv. Biology Chapter 21 Test Review

Aa, DD, bB, yy are all examples of

• genotypes
• phenotypes

AA and Aa always show up as

• dominant
• recessive

Which of the following genotypes is homozygous dominant?

• A
• Aa
• AA
• aa

Which of the following genotypes is heterozygous?

• Bb
• BB
• bb
• B

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

• recessive
• dominant
• lower case letter
• both 

A heterozygous long-tusked elephant is crossed with a homozygous recessive short-tusked elephant. What is the probability of the offspring having short tusks?

• 0%
• 25%
• 50%
• 75%

In mice, black fur (B) is dominant to white fur (b). According to the Punnett square shown, the offspring in box 4 would:

• be white.

• be heterozygous.

• be gray.

• be homozygous.

In mice, black fur (B) is dominant to white fur (b). According to the Punnett square shown, how many offspring would be black?

• 0

• 1

• 2

• 3

• 4

What goes in box 3

• Aabb
• AABB
• AAbb
• aaBb

What goes in box 15

• aabb

• AABB

• aaBB

• AAbb