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Genetics Quiz

Total questions: 25

Worksheet time: 50mins

Name
Class
Date
1.

In guinea pigs, the allele for black fur (B) is dominant. The allele for brown fur is recessive. Two guinea pigs were crossed as shown in the Punnett square. Which describes the phenotypes of the parent guinea pigs?

a)

Both parents have black fur

b)

Both parents have brown fur

c)

One parent has black fur and the other has brown fur

d)

One parent has black fur and the other has black and brown spotted fur

2.

Which of the following can be concluded about the genes for each parent?

a)

Both parents are heterozygous

b)

Both parents are homozygous recessive

c)

Both parents are homozygous dominant

d)

One parent is heterozygous and one his homozygous

3.

A capital letter indicates a/an __allele.

a)

dominant

b)

recessive

c)

mutant

d)

superior

4.

T/F: A recessive allele is expressed if there is no dominant allele.

a)

true

b)

false

5.

The two alleles in a genotype are the same.

a)

dominant

b)

recessive

c)

homozygous

d)

heterozygous

6.

The __refers to the allele combination for particular genes while the __ is the expression of that allele combination.

a)

phenotype--karyotype

b)

phenotype--genotype

c)

genotype--phenotype

d)

genotype--karyotype

7.

In humans, B is the allele for brown eyes and b is the allele for blue eyes. Two brothers both have brown eyes, but one of them has both the B and b alleles while the other only has B alleles. Which statement is true about the brothers?

a)

they have the same genotype and phenotype

b)

they have different phenotypes and genotypes

c)

they have the same phenotype but different genotypes

d)

they have the same genotype but different phenotypes

8.

In horses, the gene for white hair (W) is dominant to the gene for non-white hair (w). A horse with genotype WW was crossed with a horse with a genotype of ww, as shown in the Punnett square. What percent of the offspring should be expected to have white hair?

a)

0 %

b)

50 %

c)

75 %

d)

100 %

9.

The table below shows the genotypes that result in four different blood types in humans. Based on the information in the table, which of the following describes alleles IA and IB? (sorry I cannot do superscripts)

a)

the IA and IB alleles show sex linkage

b)

the IA allele is recessive to the IB allele

c)

the IA allele is dominant to the IB allele

d)

the IA and IB alleles show codominance

10.

Traits controlled by genes on the X chromosome are said to be

a)

sex-linked

b)

incompletely dominant

c)

homozygous

d)

mutagenic

11.

Which of the following is an example of codominance in genetic traits?

a)

a tall pea plant and a short pea plant produce tall pea plants

b)

an orange cat and a black cat produce an orange and black kitten

c)

a blue-eyed man and a brown-eyed woman produce a blue eyed child

d)

a color-blind woman and a man with normal vision produce a color blind son

12.

What does heterozygous mean?

a)

An organism has the same alleles for a trait

b)

An organism has different alleles for a trait

c)

When neither allele if fully dominant, offspring is a mixture of both

d)

the different forms of a trait (hair color - brown, blonde, red)

13.

If red snapdragon (RR) and a pink snapdragon (RW) were crossed, what percentage of the offspring would be white?

a)

0%

b)

25%

c)

50%

d)

75%

14.

What term describes an organism that displays two dominant phenotypes at the same time?

a)

complete dominance

b)

incomplete dominance

c)

codominance

d)

multiple alleles

15.

Red/green colorblindness is a SEX-LINKED recessive trait. A woman who is a carrier for this allele marries a normal vision male. What is the probability that they will have a CHILD who is colorblind?

a)

25%

b)

50%

c)

75%

d)

100%

16.

A father is homozygous A blood while the mother is heterozygous B blood. What are the chances of the couple having offspring with AB blood?

a)

0%

b)

25%

c)

50%

d)

100%

17.

Colorblindness is a sex linked recessive trait. A punnett square is completed for you. What percentage of the female offspring will be a carrier for this recessive disease?

a)

0%

b)

25%

c)

50%

d)

100%

18.

Hemophilia is a recessive x-linked disorder. A male who has hemophilia has a child with a woman who is homozygous dominant for the trait. What percentage of offspring will have the disorder?

a)

0%

b)

25%

c)

50%

d)

100%

19.

Jackie is heterozygous. If B is for brown hair, and b is for blonde hair, what is Jackie's phenotype?

a)

Brown hair

b)

Brown and blonde hair

c)

Blonde hair

d)

Black hair

20.

What is the difference between codominance and incomplete dominance?

a)

They are essentially the same

b)

Codominance always show up, incomplete dominance sometimes show up

c)

Codominance shows traits of both genes, incomplete dominance shows a mix

d)

Codominance need two genes, incomplete dominance only needs one

21.

In a particular plant, dark green leaves are a dominant trait. Plants with light green leaves have the recessive alleles. Which of the boxes marked 1-4 correspond to plants with dark leaves?

a)

1 only

b)

2 and 3

c)

1, 2 and 3

d)

4 only

22.

Which of the following is an example of a homozygous genotype?

a)

Rr

b)

NN

c)

Nr

d)

RN

23.

A red rose was crossed with a white rose and produced the pink rose seen in the picture. What type of inheritance is described?

a)

complete dominance

b)

codominance

c)

incomplete dominance

d)

multiple alleles

24.

In chickens, feather color is codominant. If a black chicken (BB) is mated with a speckled--black and white--(BW), what are the chances of having a chicken that is black?

a)

0%

b)

25%

c)

50%

d)

100%

25.

In Andalusian fowls, black individuals (BB) and white individuals (WW) are homozygous. Heterozygous individuals are gray (BW). Cross a black fowl white fowl and determine the phenotype ratio.

a)

4 black : 0 gray : 0 white

b)

0 black : 4 gray : 0 white

c)

4 BB : 0 BW: 0 WW

d)

0 BB : 4 BW: 0 WW