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Unit4Test_Genetics_Review

Total questions: 85

Worksheet time: 1hrs 3mins

Name
Class
Date
1.

  Genetically identical plants will produce either pink flowers or blue flowers, depending on the pH of soil in which they are planted. What is most likely the explanation for the differences in flower color?  

a)

The flower-color gene is codominant.

b)

Mutations alter the flower-color gene.

c)

The flower-color gene is sex-linked.

d)

Environmental factors affect flower color.

2.

What are the phenotype percentages of the offspring?

(A-Brown fur color; a-white fur color)

a)

25 % Brown fur and 75% White fur

b)

50 % Brown fur and 50% White fur

c)

75 % Brown fur and 25% White fur

d)

50% White fur and 50% Brown fur

3.

Epigenetics is the study of how DNA interacts with other molecules in the cell to

a)

change DNA

b)

turn genes on or off

c)

make more DNA

d)

stop making proteins

4.

  In pea plants, the allele for smooth seeds (R) is dominant to the allele for wrinkled seeds (r). Two parent plants are crossed. Almost half of the offspring have smooth seeds, while the rest of the offspring have wrinkled seeds. Which of the following identifies the most likely genotypes of the two parent plants?  

a)

RR and rr

b)

RR and Rr

c)

Rr and rr

d)

Rr and Rr

5.

  In Labrador retrievers, the allele for brown coat color (b) is recessive to the allele for black coat color (B). Information about two Labrador retrievers is given below.     If dog W and dog X were crossed, what percentage of the offspring would be expected to be brown?

a)

0%

b)

25%

c)

50%

d)

100%

6.

According to Mendel’s law of dominance, which statement best describes the result of a cross between parents with genotypes Rr and Rr?   ( R = red flowers r = white flowers)

a)

All offspring with at least one R will have red flowers.

b)

Only RR offspring will have red flowers.

c)

Only Rr offspring will have red flowers.

d)

Because of the law of dominance, all offspring will have red flowers.

7.


According to Mendel’s law of dominance, we would expect _________ percent of the offspring to have white flowers.

a)

0%

b)

25%

c)

50%

d)

100%

e)

75%

8.

Which of the following is true about Gregor Mendel.  Check all that apply

a)

he is known as the "father of genetics'

b)

he discovered that the shape of DNA is a double helix

c)

he experimented with pea plants

d)

He discovered sex linked traits

9.

What is the phenotype in the bottom right square? 

a)

yy

b)

Yy

c)

yellow

d)

green

10.

Red flowers crossed with white flowers can yield pink flowers. Pink is the heterozygous condition in a trait that shows incomplete dominance. If pink flowers are crossed with white flowers, assuming random chromosome segregation, what percentage is expected to be red flowers?

a)

0%

b)

25%

c)

50%

d)

75%

e)

100%

11.

Solve using incomplete dominance. A black cat (BB) mates with a white cat (WW), 100% of the offspring will be -

a)

BB-black kittens

b)

BW-gray kittens

c)

WW-white kittens

d)

BW-black and white kittens

12.

Some unique color patterns are inherited by  which type of inheritance?

a)

codominance

b)

sex-linked

c)

incomplete dominance

d)

polygenic inheritance

13.

Some unique color patterns are inherited by  which type of inheritance?

a)

codominance

b)

sex-linked

c)

incomplete dominance

d)

polygenic inheritance

14.

What is the genotype of the mother?

a)

BB

b)

bb

c)

Bb

d)

BB or Bb

15.

There are 4 different alleles for blood types out there for you to inherit.  You however only inherit 2 alleles (one from your mother and one from your father)  There for human blood type is an example of

a)

incomplete dominance

b)

multiple alleles

c)

sex-linked traits

d)

polygenic inheritance

16.

Human blood types are unusual because you could have blood type AB.  AB blood type is an example of 

a)

incomplete dominance

b)

multiple alleles

c)

codominance

d)

polygenic inheritance

17.

What is a Punnett square used for?

a)

predicting the probability of genetic outcomes

b)

to give you the actual percentages of genetic traits you will see in offspring

c)

it is actually another word for pedigree

18.

Arctic hares are white for part of the year and brown the other part of the year.  This color change is due to: 

a)

incomplete dominance

b)

codominance

c)

recessive inheritance

d)

dominant inheritance

e)

environmental factors

19.

Which of the following describes epigenetics?

a)

changes to DNA that can not be inherited by offspring

b)

spontaneous mutations that can be inherited by offspring

c)

heritable traits in gene expression turned on by environmental factors

20.

A mutation may be passed along to human offspring

a)

through mitosis only.

b)

through neither mitosis nor meiosis.

c)

through both mitosis and meiosis.

d)

through meiosis only.

21.


In the image, the squares represent males, the circles females. The darkened shapes represent those who are affected. The diagonal line represents deceased subjects.
In the diagram below, the trait being documented is inherited which way?

a)

dominant trait

b)

recessive trait

c)

sex-linked trait

d)

codominance

22.

In the diagram below, the trait being documented is inherited which way?

a)

recessive trait

b)

dominant trait

c)

sex-linked trait

d)

polygenic inheritance

23.

Coat color in mice is incompletely dominant. Yellow (Y) and white (W) -colored mice are homozygous, while cream-colored mice are heterozygous (YW). If two cream-colored mice mate, what percentage of each mice will be cream color?

a)

25%

b)

50%

c)

0%

d)

75%

e)

100%

24.

What is the probability of having a AB blood type when the MOM= O and Dad= AB?

a)

25%

b)

50%

c)

0%

d)

75%

e)

100%

25.


This pedigree represents the inheritance of a non sex-linked trait in this family. How many of the females have the trait?

a)

2

b)

3

c)

5

d)

6

26.

Sex linked traits are found on what chromosome?

a)

x

b)

y

c)

x & y

d)

trisomy 21

27.

Cross a male with hemophilia(sex-linked) and a female carrier. What is the chance of having a son with hemophilia?

a)

0%

b)

25%

c)

50%

d)

75%

e)

100%

28.

Colorblindness is an X-linked recessive disorder. A man who is colorblind can give the colorblind allele to his _____.

a)

son

b)

daughter

c)

both son and daughter

d)

neither son or daughter

29.

In snapdragons, flower color is controlled by incomplete dominance. The two alleles are red (R) and white (W). The heterozygous genotype is expressed as pink. What happens when you cross a Red flower with a pink flower?

a)

100% red

b)

50% red, 50% white

c)

50% red, 50% pink

d)

25% red, 50% pink, 25% white

e)

100% white

30.

The production of pink flowered plants from a cross between a red flowered plant and a white flowered plant is an example of

a)

polygenic inheritance

b)

codominance

c)

incomplete dominance

d)

sex-linked traits

31.

In pea plants, purple flowers (P) are dominant over white flowers (p). If two heterozygous purple-flowered plants are crossed with each other, then what are the possible genotypes of the offspring?

a)

PP and pp

b)

Pp, PP and pp

c)

Pp only

d)

Pp and pp

32.

Non-Mendelian inheritance patterns can be sorted into three categories: incomplete dominance, codominance, and sex-linked traits. Which are NOT an example of a sex-linked trait? (more than 1 answer)

a)

Hemophilia

b)

Colorblindness

c)

Dog tail length

d)

Down's syndrome

33.

An individual who is a

heterozygous carrier for the Sickle Cell Trait (SCT) provides protection against Malaria without being affected by Sickle Cell Anemia. If one parent who is homozygous for SCT and one parent with normal blood have offspring what is the probability that their offspring will have protection against Malaria by being carriers of SCT?

a)

0%

b)

25%

c)

50%

d)

75%

e)

100%

34.

According to Mendel's law of segregation, what is the expected genotypic ratio of the offspring when two heterozygous individuals are crossed?

a)

1:1

b)

1:2:1

c)

3:1

d)

9:3:3:1

35.

What is the expected genotypic ratio of the offspring when two heterozygous individuals are crossed?

a)

1:1

b)

1:2:1

c)

3:1

d)

9:3:3:1

36.

What is the probability of having a BB blood type when the MOM= O and Dad= AB?

a)

25%

b)

50%

c)

0%

d)

75%

e)

100%

37.

What is the probability of having a BB blood type when the MOM= O and Dad= AB?

a)

25%

b)

50%

c)

0%

d)

75%

e)

100%

38.

According to Mendel’s law of dominance, which statement best describes the result of a cross between parents with genotypes Rr and Rr?   ( R = red flowers r = white flowers)

a)

All offspring with at least one R will have red flowers.

b)

Only RR offspring will have red flowers.

c)

Only Rr offspring will have red flowers.

d)

Because of the law of dominance, all offspring will have red flowers.

39.

What is the probability of having a AB blood type when the MOM= O and Dad= AB?

a)

25%

b)

50%

c)

0%

d)

75%

e)

100%

40.

How can epigenetic changes influence an organism's phenotype without altering the DNA sequence?

a)

By changing the DNA sequence to produce new traits

b)

By modifying gene expression through DNA methylation

c)

By increasing the number of genes in the genome

d)

By removing essential genes from the genome

41.

Which of the following environmental factors can lead to epigenetic changes?

a)

Temperature and humidity

b)

Diet and exercise

c)

Exposure to pollutants

d)

All of the above

42.

What role do histone modifications play in epigenetics?

a)

They change the DNA sequence to alter gene expression

b)

They replicate DNA more efficiently

c)

They influence the packing of DNA, affecting gene expression

d)

They eliminate foreign DNA from the cell

43.

If a plant heterozygous for tallness (Tt) is crossed with a homozygous recessive plant for the same trait, what is the expected phenotype ratio of their offspring?

a)

100% tall

b)

75% tall, 25% short

c)

50% tall, 50% short

d)

25% tall, 75% short

44.

Which of the following is an example of a trait that follows Mendelian inheritance patterns?

a)

Human height

b)

Pea plant flower color

c)

Skin color in humans

d)

Eye color in fruit flies

45.

Which of the following is an example of codominance in humans?

a)

Blood type AB

b)

Attached earlobes

c)

Blue eye color

d)

Height

46.

In cattle, the allele for red coat (R) and the allele for white coat (W) are codominant. If a red cow (RR) is crossed with a white bull (WW), what will be the coat color of the offspring?

a)

Red

b)

White

c)

Roan (mixed red and white)

d)

Black

47.

How does codominance differ from incomplete dominance?

a)

In codominance, one allele is dominant over the other.

b)

In codominance, both alleles are expressed equally in the phenotype.

c)

In incomplete dominance, the phenotype is a blend of the two alleles.

d)

Both B and C are correct.

48.

When a red snapdragon is crossed with a white snapdragon, the offspring are pink. What is this an example of?

a)

Co-dominance

b)

Incomplete dominance

c)

Multiple alleles

d)

Sex-linked inheritance

49.

In the case of incomplete dominance, if a homozygous red-flowered plant is crossed with a homozygous white-flowered plant, what will be the phenotype of the F1 generation?

a)

All red flowers

b)

All white flowers

c)

A mix of red and white flowers

d)

All pink flowers

50.

What is the purpose of using pedigree charts in genetics?

a)

To predict the weather patterns over generations

b)

To trace the inheritance of traits in families

c)

To map out the physical locations of genes on chromosomes

d)

To determine the nutritional needs of an organism

51.

In a pedigree chart, what does a square typically represent?

a)

A female individual

b)

A male individual

c)

A marriage or mating

d)

An offspring

52.

How can a pedigree chart help in predicting the risk of inheriting genetic disorders?

a)

By showing the weather conditions affecting genetic mutations

b)

By indicating the presence of dominant or recessive traits in ancestors

c)

By displaying the nutritional habits of ancestors

d)

By mapping the entire genome of an individual

53.

Which of the following is an example of a sex-linked trait in humans?

a)

Blood type

b)

Eye color

c)

Color blindness

d)

Height

54.

Why are males more likely than females to express recessive sex-linked traits?

a)

Males have two copies of each sex chromosome.

b)

Males are genetically predisposed to recessive traits.

c)

Males have only one X chromosome.

d)

Females cannot inherit sex-linked traits.

55.

How can a female be a carrier of a sex-linked trait but not express it?

a)

She has two dominant alleles for the trait.

b)

She has one recessive allele and one dominant allele for the trait.

c)

She has two recessive alleles for the trait.

d)

She cannot be a carrier without expressing the trait.

56.

What principle of Mendel's explains why alleles separate during gamete formation?

a)

Law of Independent Assortment

b)

Law of Segregation

c)

Law of Dominance

d)

Law of Uniformity

57.

Which of Mendel's laws can be demonstrated by a dihybrid cross?

a)

Law of Segregation

b)

Law of Independent Assortment

c)

Law of Dominance

d)

Law of Uniformity

58.

Check all the blood types that exist in humans.

a)

A

b)

B

c)

AB

d)

O

59.

What would be the gametes for the YyRr plant?

a)

YR, YR, yR, yR

b)

YR, Yr, yR, yr

c)

Yy, Rr, YY, RR

d)

yy, rr, yy, rr

60.

What would be the gametes for the yyrr plant?

a)

yR, yr, Yr, YR

b)

yy, yy, yy, yy

c)

yr, yr, yr, yr

d)

YR, YR, YR, YR

61.

Which of the following represents a heterozygous genotype?

a)

Aa

b)

AA

c)

aa

d)

Ab

62.

Which of the following best describes Mendel's law of dominance?

a)

When an organism has two different alleles of the same gene, both genes will be expressed equally.

b)

When an organism has two alleles, one of genes will be expressed and the other will be hidden.

c)

When an organism has two different alleles of the same gene, one will always be dominant.

d)

The stronger of the two genes will be expressed.

63.

Mendel also observed seed color in pea plants. In a study of several generations, yellow seeds appeared more frequently than green seeds. Which of the following is most likely the reason for this observation?

a)

Green seeds are dominant to yellow seeds.

b)

Yellow seeds are recessive to green seeds

c)

Green seeds are recessive to yellow seeds.

64.
If a trait is homozygous the letters are the 
a)
Same
b)
Different
65.
If you are homozygous recessive, the genotype would be 
a)
AA
b)
aa
c)
Aa
66.
Another term for homozygous is
a)
Hybrid 
b)
Purebred
c)
Recessive
d)
Dominant
67.
Another term for heterozygous is
a)
Hybrid
b)
Purebred
c)
Dominant
d)
Recessive
68.
The law that states that when an organism is hybrid for a pair of contrasting traits, the dominant trait is the one that is shown. 
a)
Law of Dominance
b)
Law of Independent Assortment
c)
Law of of Segregation
d)
Law of Incomplete Dominance
69.
 Gregor Mendel developed some basic principles of heredity by ______________.
a)
breeding fruit flies
b)
cutting off the tails of mice
c)
crossing pea plants
d)
growing bacteria in a laboratory
70.
How many females are in this pedigree?
a)
3
b)
4
c)
6
d)
7
71.
How many of the males in this pedigree show the trait being studied?
a)
2
b)
3
c)
4
d)
6
72.
When 2 pea plants heterozygous for height (Tt) are crossed, what is the ratio of the resulting genotypes (TT:Tt:tt)?
a)
1:2:1
b)
2:1:1
c)
0:3:1
d)
0:2:2
73.
 Look at the Punnett square. If the two parents represented in the Punnett square have four offspring, what does the Punnett square tells you?
a)
two of the offspring will definitely be heterozygous.  
b)
one of the offspring will definitely show the recessive trait.
c)
there is a 50% chance for each of the 4 offspring to have the genotype Rr.
d)
there is a greater chance for the offspring to be RR than rr.
74.

Colorblindness is a recessive X-linked disorder.

Which genotype represents a male with normal vision?

a)

XN YN

b)

Xn Yn

c)

XN Y

d)

Xn Y

75.
Different variations of a gene are called?
a)
Alleles
b)
DNA
c)
Chromosome
d)
Gene
76.

The blending of two traits in which one is not completely dominant over the other is known as ---

a)

incomplete dominance

b)

codominance

77.

What type of inheritance pattern is shown here?

a)

Codominance

b)

Incomplete dominance

78.

A calico cat shows both the traits for orange fur and black fur. What kind of allele expression is this?

a)

Incomplete dominance

b)

Codominance

79.

The green fish offspring in this image is an example of ---

a)

Incomplete dominance

b)

Codominance

80.

Incomplete dominance occurs in cats, which allows them to be Black, White, or gray as shown on this Punnett square. What percentage of the offspring will be gray?

a)

25

b)

50

c)

75

d)

100

81.

What does this Punnett square and the probabilities of the ofspring represent?

a)

incomplete dominance

b)

codominance

82.

A brown rooster and a white chicken produced this speckled offspring:

a)

Incomplete dominance

b)

Codominance

c)

Complete dominance

83.

A black male and white female produced this grey offspring:

a)

Incomplete dominance

b)

Codominance

c)

Complete dominance

84.

A woman with curly hair and a man with straight hair produced a child with wavy hair:

a)

Incomplete dominance

b)

Codominance

c)

Complete dominance

85.

What are the possible genotypes for a person who has the blood group A?

a)

IAIA

b)

IAIi

c)

IAIB

d)

IBIi