Download Monohybrid Punnett Square Practice

Monohybrid Punnett Square Practice
1. Freckles are dominant over no freckles. Using the letter F, cross two heterozygous individuals.
2. Widow’s peak is dominant to an even hairline. Use the letter W and cross a female with an even hairline with a
male who is homozygous for a widow’s peak.
3. Brown eyes are dominant over blue eyes. Cross a male and a female who each have brown eyes and are known
to be homozygous for this trait.
4. Tall pea plants are known to be dominant over short pea plants. Cross two tall heterozygous pea plants.
5. White is recessive to a black coat in guinea pigs. Cross a heterozygous male with a white female guinea pig.
6. In sheep, white coats are due to a dominant gene while black coats are due to a recessive gene. A white ewe is
mated with a black ram and the result is a black lamb. If they produced another offspring, could it be white? If
so, what are the chances of it being white?
7. Our bumblebee has a long stinger. This trait is dominant over short stingers. A cross with a neighbor’s bee
always produces an equal number of offspring with short stingers as those with long stingers. What is the
genotype of each parent?
BONUS:
1. A brown mink is crossed with a sliver blue mink. Offspring are always brown. When these offspring are crossed
among themselves, they produced 47 brown mink and 15 silver blue mink. Which of these traits is dependent
upon a dominant gene? What would the parent genotypes have to be to produce this offspring?
2. In humans green eye color is recessive to brown eyes. For answering this question you can assume that eye
color is determined by a single locus with two alleles, one for brown (B) and one for green (b). Bill has brown
eyes and he marries Yolanda, who has green eyes. Bill and Yolanda have 15 children, all of whom have brown
eyes. Yolanda’s mother and father had brown eyes. Bill’s mother had brown eyes, but he cant remember what
color eyes his father had.
a. What is the eye color of Bill’s father?
b. The possible genotype’s for the following are:
i. Bill ii. Yolanda - iii. Bill’s mom - iv. Bill’s dad - v. Yolanda’s mom vi.Yolanda’s dad –