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Monohybrid and Dihybrid Crosses

Total questions: 35

Worksheet time: 51mins

Name
Class
Date
1.
Which of the following is a phenotype?
a)
BB
b)
Bb
c)
bb
d)
Blue eyes
2.
What is a phenotype
a)
The genetic make up (code)
b)
The physical trait
3.
having two of the same genes for the trait (sometimes called purebred).
a)
homozygous
b)
hetrozygous
c)
protein
d)
chromosome
4.
having two different genes for a trait (sometimes called hybrid).
a)
protein
b)
homozygous
c)
heterozygous
d)
genotype
5.
An allele whose trait only shows up when no dominant allele is present.
a)
hidden allele
b)
dominant allele
c)
recessive allele
d)
present allele
6.
Which of the following genotypes would be considered heterozygous?
a)
BB
b)
gg
c)
Ff
d)
TT
7.
Which of the following alleles is homozygous recessive?
a)
Tt
b)
tt
c)
TT
d)
T
8.

The passing of genetic traits from parent to offspring is known as

a)

heredity

b)

trait

c)

gene

d)

allele

9.
A dog gives birth to 5 puppies. What percentage of the chromosomes does each puppy share with the mother?
a)
25%
b)
50%
c)
75%
d)
100%
10.

What predicts genetic outcomes?

a)

genetic engineering

b)

punnet square

c)

probability

11.

What is ratio of the offspring from the cross shown will be homozygous recessive for the trait of tallness? T = tall t = short

a)

0 in 4

b)

1 in 4

c)

2 in 4

d)

4 in 4

12.

Brown eyes are dominant over blue eyes. What is the probability that the offspring will have brown eyes in this cross?

a)

25%

b)

50%

c)

75%

d)

100%

13.

Identify all the DOMINANT alleles

14.

In mice, black fur (B) is dominant to white fur (b). According to the Punnett square shown, the offspring in box 4 would:

a)

be white.

b)

be heterozygous.

c)

be gray.

d)

be homozygous.

15.

In mice, black fur (B) is dominant to white fur (b). According to the Punnett square shown, how many offspring would be black?

a)

0

b)

1

c)

2

d)

3

e)

4

16.

What are the possible phenotype(s) of the offspring? (A-Brown hair; a-blond hair)

a)

50 % Brown Hair and 50% Blond Hair

b)

25 % Brown Hair and 75% Blond Hair

c)

75 % Brown Hair and 25% Blond Hair

d)

0% Brown Hair and 100% Blond Hair

17.

Brown eyes are dominant over blue eyes. What is the probability that the offspring will have brown eyes in this cross?

a)

25%

b)

50%

c)

75%

d)

100%

18.

Long fur (L) is dominant to short fur (l) in rabbits. Which rabbits would have long fur?

a)

LL

b)

Ll

c)

ll

19.
Question Image

Having a Widow's Peak is dominant (W) over not having one (w). If parent A (WW) and parent B (ww) have a child, what is the likelihood that--

a)

The child will have a widow's peak

1.

100%

b)

The child will not have a widow's peak

2.

0%

c)

The genotype of these children

3.

Ww

20.

T - tall and t = short. In the Punnett square below, what belongs in the missing square (a)  

Choose from the below words
tt
Tt
Bb
TT
21.
Question Image

Match the following genotypes with their descriptions.

a)

Homozygous dominant

1.

Genotype TT

b)

Heterozygous

2.

Genotype Tt

c)

Homozygous recessive

3.

Genotype tt

22.
Hair colour is an example of
a)
genotype
b)
phenotype
23.

In a genetic cross between two heterozygous individuals (Bb), what is the probability of producing a homozygous recessive offspring?

a)

50%

b)

25%

c)

0%

d)

75%

24.

Which of the following is an example of a genotype?

a)

Tall

b)

Blue eyes

c)

Short

d)

Tt

25.

In a cross between a homozygous dominant and a homozygous recessive individual, what will be the phenotype of the offspring?

a)

All recessive

b)

All dominant

c)

50% dominant, 50% recessive

d)

75% dominant, 25% recessive

26.

This is a Dihybrid Punnett Square. It has 16 boxes and crosses 2 traits instead of one. Use your knowledge of how to write genotypes and fill in the first row with the correct genotypes.

27.

Select the boxes in the Punnett Square where you would find heterozygous offspring.

28.

A white mouse with red eyes is crossed with a black mouse with brown eyes. The white mouse is recessive for both of its traits. The black mouse is dominant for both of its traits.

This cross would be

a)

BBEE x bbee

b)

BBEe x BbEe

c)

BbEE x BbEe

d)

BBee x BBEE

29.
What goes in box 3
a)
Aabb
b)
AABB
c)
AAbb
d)
aaBb
30.

What goes in box 15

a)

aabb

b)

AABB

c)

aaBB

d)

AAbb

31.
Using the dihybrid cross and key provided, what is the probability of the offspring being tall and white?
a)
9
b)
2
c)
3
d)
6
32.

Based off this punnett square, what fraction of the offspring will have wrinkled, yellow seeds?

a)

9/16

b)

3/16

c)

1/16

d)

16/16

33.
What goes in box 6
a)
AaBB
b)
AABB
c)
aaBB
d)
AAbb
34.

What is Mendel's Law of Independent Assortment?

a)

If the recessive allele is passed for one trait, then it is more likely that the recessive allele will be passed for the other trait.

b)

The passing of allele of one trait does not affect the passing of allele of another trait.

c)

If the dominant allele is passed for one trait, then it is more likely that the dominant allele will be passed for the other trait.

d)

If the dominant allele is passed for one trait, then it is more likely that the recessive allele will be passed for the other trait.

35.

Mendel's Law of Segregation means?

a)

Every person has two alleles for each trait, they segregate from each other and the dominant is passed more often.

b)

Every person has two alleles for each trait, Where two traits are being passed, they do not effect each other.

c)

Every person has two alleles for each trait, they segregate from each other and are passed down at random.

d)

Every person has two alleles for each trait, they segregate from each other and the recessive is passed more often.