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Genetics and Punnett Squares (9.19)

Total questions: 20

Worksheet time: 3hrs 20mins

Name
Class
Date
1.
In pea plants, the tall allele is dominant to the short allele. What key would demonstrate this?
a)
Tall = T
Short = S
b)
Tall = T
Short = t
c)
Tall = t
Short = T
d)
Tall = TT
Short = tt
2.
In a heterozygous genotype, the ___________ allele takes over in the phenotype.
a)
recessive
b)
dominant
c)
lower case letter
d)
both 
3.
Dominant alleles are represented by a:
a)
Male gene
b)
lowercase letter
c)
recessive trait
d)
capital letter
4.

Identify the homozygous dominant genotype:

a)

FF

b)

Ff

c)

ff

d)

fF

5.

Which of the following would be a phenotype?

a)

Aa

b)

red hair

c)

heterozygous

d)

aa

6.
Which of the following genotypes is heterozygous?
a)
Bb
b)
BB
c)
bb
d)
B
7.

Which of the following genotypes is homozygous dominant?

a)

Yy

b)

yY

c)

yy

d)

YY

8.

Which of the following genotypes is homozygous recessive?

a)

Tt

b)

tt

c)

TT

d)

tT

9.

Which choice best represents the genotypic ratios for the offspring of this cross?

a)

1 Yy: 2 yy: 0 YY

b)

2 Yy: 2 yy: 0 YY

c)

3 Yy: 1 yy: 0 YY

d)

1 Yy: 3 yy: 0 YY

10.

Fill in the Yellow Box

a)

AA

b)

Aa

c)

aa

d)

none of these

11.

Fill in the Yellow Box

a)

Bb

b)

BB

c)

bb

d)

none of these

12.

What is the probability that the offspring born from this cross will have a homozygous dominant genotype?

a)

25%

b)

50%

c)

75%

d)

100%

13.

The punnett square is used to tell the color of a frogs skin. "G" means green skin and "g" means brown skin. What is the probability the baby frogs from this cross will have brown skin?

a)

0%

b)

25%

c)

50%

d)

100%

14.

Purple (P) is dominant to the white (p).

According to the Punnett Square, what is the probability of an offspring being purple?

a)

25%

b)

0%

c)

100%

d)

50%

15.
What is the yellow seed genotype?
a)
aa
b)
Aa
c)
AA
d)
AA or Aa
16.

What is the dominant trait?

a)

yellow pea seeds

b)

green pea seeds

c)

there is no dominant seed

d)

Jolly green giant

17.

What are the genotypic probabilities for the offspring of this cross?

a)

25% blue eye 75 % brown eye

b)

BB = 25% Bb = 50% bb = 25%

c)

BB= 50 % bb = 50%

d)

All brown eye

18.
What are the parents' genotypes?
a)
Homozygous for brown eyes
b)
Heterozygous for brown eyes
c)
Homozygous for blue eyes
d)
Heterozygous for blue eyes
19.
What is the phenotype for the recessive trait?
a)
brown eyes
b)
green eyes
c)
blue eyes
20.
A section of the DNA strand that determines a specific trait
a)
gene
b)
trait
c)
chromosome
d)
allele