Hardy Practice Problems Set 2
1. Let Y = yellow flowers, y = purple flowers. The frequency of the Y allele is .8.
a. What is the frequency of the y allele?
b. How many yellow flowers will there be in a population of 6,000? purple?
2. The frequency of the r allele for white color in snapdragons is 10%.
(Reminder: Snapdragons exhibit incomplete dominance. RR - red, Rr - pink, rr – white)
a. How many flowers will be white out of 5,000? pink? red?
b. I have a mixed bag of seeds and need to raise 2,000 white snapdragons for summer weddings.
i. How many seeds should I plant?
ii. How many pink flowers will I have to sell?
iii. How many red flowers will I have to sell?
iv. Is it important for this flower breeder to do some test crosses first? Why?
3. The frequency of the X-linked gene for hypertrichosis (extra hair follicles) .004%.
a. How many males would be affected out of 1,000,000 males?
b. How many females would be affected out of 1,000,000 females?
c. How many females would be carriers out of 1,000,000 females?
4. Four thousand males in Fort Collins (population 100,000) suffer from X-linked red-green color
blindness. How many color blind females would you expect in this town? (Assume that the population
of Fort Collins is 50% male and 50% female)