Hardy Weinberg Problems
In a population of 100 pea plants, 16 show the
recessive trait of green seeds. Tell the
following:
a. The frequency of Y ________
b. The frequency of y ________
c. % of population that is homozygous dominant
_______
d. % of population that is heterozygous _______
e. % of population that is homozygous recessive
_______
f. % of population with yellow seeds _________
a.
b.
c.
d.
e.
f.
0.6
0.4
36%
48%
16%
84%
In a population of 100,000 people, 36,000
cannot roll their tongue, a recessive trait.
Tell the following:
a.
b.
c.
d.
e.
f.
g.
The frequency of R ________
The frequency of r ________
% of population that is homozygous dominant _______
% of population that is heterozygous _______
% of population that is homozygous recessive
_______
% population can roll tongue _________
% population cannot roll tongue __________
a.
b.
c.
d.
e.
f.
g.
0.4
0.6
36%
48%
16%
64%
36%
If the frequency of the dominant allele is 0.5,
answer the following:
a. What is the frequency of the recessive allele?
__________
b. What is the percentage of individuals with the
homozygous dominant genotype? _______
c. What is the percentage of individuals with the
heterozygous genotype?________
d. In a population of 5000, how many are
heterozygous?
e. In a population of 200, how many are
homozygous recessive? ____________
a.
b.
c.
d.
e.
0.5
25%
50%
2500
50
In snails, shell color can be dark, medium, or
light. In a population of 300 snails, 192
have dark shells.
a. The frequency of S ________
b. The frequency of s ________
c. % of population that is homozygous dominant
_______
d. % of population that is heterozygous _______
e. % of population that is homozygous recessive
_______
a.
b.
c.
d.
e.
0.8
0.2
64%
32%
4%
In a population of 500,000 rabbits, 405,000
show the dominant phenotype of a bent
ear. Determine the following:
a. The frequency of E ________
b. The frequency of e ________
c. % of population that is homozygous dominant
_______
d. % of population that is heterozygous _______
e. % of population that is homozygous recessive
_______
a.
b.
c.
d.
e.
0.56
0.44
31.36%
49.28%
19.36%
Suppose that one gene locus determines
stripe patterns ins skunks. SS skunks
have two broad stripes; Ss skunks
have two narrow stripes; ss skunks have
white speckles down their backs. A
sampling of a population of skunks
found 65 broad-striped skunks;
14 narrow-striped, and 1 speckled.
Determine the allele frequencies.
S = _______
s = _______
In a population of 200 mice, 98 are
homozygous dominant for brown coat
color (BB), 84 are heterozygous,
and 18 are homozygous recessive.
a. The allele frequency for B = ______
b. The allele frequency for b = ______
c. The genotype frequencies for this
population are _____ BB, _______ Bb,
and ______bb.
a. p = .7
b. q = .3
c. 49% BB
42% Bb
9% bb