Punnett Squares and Pedigrees

Which of the following is a phenotype?

• Aa
• red hair
• heterozygous
• DNA

A red flowered plant (RR) breeds with a White flowered plant (WW). The gene for petal color in these plants expresses codominance.  What percentage of the offspring will have red and white (RW) flowers?

• 0%
• 25%
• 50%
• 100%

Which of the following genotypes is heterozygous?

• Bb
• BB
• bb
• B

Which of the following is homozygous dominant?

• Yy
• Y
• yy
• YY

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

In a pedigree chart, what does a half-filled circle represent?

• A carrier female

• An affected male

• A carrier male

• An unaffected female

If a trait is controlled by a dominant allele, what is the expected phenotype of an organism with a heterozygous genotype?

• Intermediate

• Cannot be determined

• Dominant

• Recessive

Aa is

• homozygous
• heterozygous

Looking at this pedigree, how many family members have the disease?

• 4
• 7
• All
• None

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

• recessive
• dominant
• lower case letter
• both