Punnett Square

Which statement describes how two organisms may show the same trait, yet have different genotypes for that phenotype?

• Both are homozygous for the dominant trait.
• One is homozygous dominant, and the other homozygous recessive.
• Both are heterozygous for the dominant trait.
• One is homozygous dominant and the other heterozygous.

A female guinea pig homozygous dominant for black fur color is mated with a male homozygous for white fur color. In a litter of eight offspring, probability would predict there would be _____.

• 8 black guinea pigs  
• 4 black and 4 white guinea pigs  
• 2 black, 4 gray, and 2 white guinea pigs  
• 8 white guinea pigs

The type of inheritance pattern shown when a black-feathered chicken is crossed with a white-feathered chicken, which produces only grey-feathered chickens is _____.

• inbreeding  
• polygenic inheritance
• codominance
• incomplete dominance

Eye color in fruit flies is a sex-linked condition. If a female fruit fly heterozygous for red eyes (XRXr) is crossed with a recessive white-eyed male (Xr Y), what percentage of their offspring would have white eyes?

• 0%  
• 50%  
• 25%
• 75%

A family has 4 children. One child is Blood Type O, one child is Blood Type AB, and the other two children are both Blood Type A. What are the genotypes of the parents?

• IAIA x IBIB
• IAi x IBi
• IAIB x IAIB
• IAIB x ii

How many pairs of chromosomes are in your cells?

• 23
• 19
• 12
• 10

Which one is an example of an allele?

• physical characteristics
• Aa
• DNA
• genotype

Which of the following alleles is homozygous dominant?

• A
• Aa
• AA
• aa

Dominant alleles are represented by a:

• Male gene
• lowercase letter
• recessive trait
• capital letter

Which of the following alleles is heterozygous?

• Bb
• BB
• bb
• B