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Science of Heredity

Total questions: 82

Worksheet time: 1hrs 23mins

Name
Class
Date
1.

A couple has two children both of whom are boys. What is the chance that the parents' next child will be a boy?

a)

0%

b)

50%

c)

25%

d)

75%

2.

A dog's phenotype can be determined by _________.

a)

Looking at the dog's parents

b)

Examining the dog's chromosomes

c)

Mating the dog and examining its offspring

d)

Looking at the dog

3.

What did Gregor Mendel do to study different characteristics in his genetics experiments?

a)

He studied only asexual plants

b)

He studied only tall and short pea plants

c)

He cross-pollinated plants

d)

He cross-pollinated both plants and animals

4.

Factors that control traits are called______.

a)

Genes

b)

Purebreds

c)

Recessives

d)

Parents

5.

Scientists call an organism that has two different alleles for a trait a __________.

a)

Hybrid

b)

Trait

c)

Purebred

d)

Factor

6.

What does the notation TT mean to geneticists?

a)

Two dominant alleles

b)

Heterozygous alleles

c)

At least one dominant allele

d)

One dominant and one recessive allele

7.

What does the notation Tt mean to geneticists?

a)

Two dominant alleles

b)

Two recessive alleles

c)

Homozygous alleles

d)

One dominant allele and one recessive allele

8.

What is probability?

a)

The actual results from a series of events

b)

A number that describes how likely it is that an event will occur

c)

The way the results of one event affect the next event

d)

The number of times a coin lands heads up

9.

What does a Punnett Square show?

a)

All the possible outcomes of a genetic cross

b)

Only the dominant alleles in a genetic cross

c)

Only the recessive alleles in a genetic cross

d)

All of Mendel's discoveries about genetic crosses

10.

If a homozygous black guinea pig (BB) is cross with a homozygous white guinea pig (bb), what is the probability that an offspring will have black fur?

a)

25%

b)

50%

c)

75%

d)

100%

11.

An organism's physical appearance is its ________.

a)

Genotype

b)

Phenotype

c)

Codominance

d)

Heterozygous

12.

What happens during meiosis?

a)

Two sex cells combine

b)

Chromosome pairs separate and are distributed into new sex cells

c)

Each sex cell copies itself to form four new chromosomes

d)

Chromosome pairs remain together when new sex cells are formed

13.

When sex cells combine to produce new offspring, each sex cell will contribute ______.

a)

One fourth the number of chromosomes in body cells

b)

Half the number of chromosomes in body cells

c)

The normal number of chromosomes in body cells

d)

Twice the number of chromosomes in body cells

14.

Which term refers to physical characteristics that are studied in genetics?

a)

Traits

b)

Offsprings

c)

Generations

d)

Hybrids

15.

The different forms of a gene are called _________.

a)

Alleles

b)

Factors

c)

Masks

d)

Traits

16.

An organism's genotype is its _______.

a)

Genetic makeup

b)

Feather color

c)

Physical appearance

d)

Stem height

17.

An organism that has two identical alleles for a trait is _______.

a)

Codominant

b)

Tall

c)

Homozygous

d)

Heterozygous

18.

An organism that has two identical alleles for a trait is _______.

a)

Codominant

b)

Tall

c)

Homozygous

d)

Heterozygous

19.

When will a recessive show its effect?

a)

Even if no recessive genes for that trait are present

b)

In the presence of one recessive gene

c)

When two recessive genes for a trait are present

d)

Only if the mother has the recessive

20.

If a homozygous dominant (FF) is crossed with a heterozygous (Ff), what is the probability that the recessive trait will emerge?

a)

100%

b)

75%

c)

25%

d)

0%

21.

When will a dominant trait show its effect?

a)

Even if no dominant genes for that trait are present

b)

In the presence of one dominant gene

c)

When two recessive genes for a trait are present

d)

Only if the mother has the trait

22.

B-black fur

b-white fur


If two heterozygous cross, which of the following is the correct phenotype for the parents' fur?

a)

Both parents have white fur

b)

Both parents have black fur

c)

The father has black and the mother has white

d)

The mother has white and the father has black

23.

What is the probability of two parents that are BB and Bb to have an offspring with a recessive trait?

a)

0%

b)

75%

c)

25%

d)

100%

24.

What type of plants did Mendel use for his experiment?

a)

Tomato

b)

Pea

c)

Flowering

d)

None of the above

25.

What type of allele represents a homozygous dominant gene?

a)

TT

b)

Tt

c)

tt

d)

tT

26.

What type of cell contains only one of each kind of chromosome?

a)

Diploid

b)

Animal

c)

Haploid

d)

None of the above

27.

When Mendel crossed purebred short plants with purebred tall plants, all of the offspring were _____________.

a)

Tall

b)

Short

28.

A hybrid is the offspring of parents that have __________ alleles for a trait.

a)

Different

b)

Same

29.

A pea plant that is _____________ for tall stems has the alleles Tt.

a)

Heterozygous

b)

Homozygous dominant

c)

Homozygous recessive

30.

A Punnett Square shows all the possible combinations of _______ resulting from a cross.

a)

Alleles

b)

Genes

31.

Chromosomes carry _________ from parent to offspring.

a)

Genes

b)

Diploid Cell

c)

Meiosis

32.

If a _______________ allele is present, its trait will appear in the organism.

a)

Dominant

b)

Recessive

33.

An organism that has two dominant or two recessive alleles is said to be _________ for that trait.

a)

Homozygous

b)

Heterozygous

34.

The process in which a parent cell divides twice to produce sex cells is called ________.

a)

Mitosis

b)

Meiosis

c)

Haploid Cell

d)

Heterozygous

35.
How many alleles (letters) do each person carry for a trait?
a)
1
b)
2
c)
3
d)
4
36.
Dominant alleles are represented by a:
a)
Male gene
b)
lowercase letter
c)
recessive trait
d)
capital letter
37.
Aa, DD, bB, yy are all examples of
a)
genotypes
b)
phenotypes
38.
B = brown eyes
b = blue eyes
What is true about these two brothers that have brown eyes?
One has genotype BB the other Bb.
a)
they have same phenotype and genotype
b)
they have different genotypes and phenotypes
c)
they have same phenotype but different genotypes
d)
they have same genotype but different phenotypes
39.
What ratio of the offspring from the cross shown will be homozygous recessive for the  trait of tallness? 
a)
0 in 4
b)
1 in 4
c)
2 in 4
d)
4 in 4
40.
Which of the following genotypes is homozygous dominant?
a)
A
b)
Aa
c)
AA
d)
aa
41.
Which of the following genotypes is heterozygous?
a)
Bb
b)
BB
c)
bb
d)
B
42.
Which of the following is homozygous dominant?
a)
Yy
b)
Y
c)
yy
d)
YY
43.
Which of the following is homozygous recessive?
a)
Tt
b)
tt
c)
TT
d)
T
44.
What you see, or the physical appearance.
a)
Genotype
b)
Phenotype
c)
Homozygous
d)
Heterozygous
45.
T - tall and t = short
In the punnett square below, what belongs in the missing square
a)
tt
b)
Tt
c)
Bb
d)
TT
46.
Which choice best represents the genotype 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
47.
What is the phenotype 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 
48.
If you have a male with large wings (DD) and a female with small wings (dd). What allele stands for large wings? 
a)
D
b)
d
c)
Dd
d)
dd
49.
A tall plant (TT) is crossed with a tall plant (Tt).  What is the genotype?
a)
2 TT: 2 Tt: 0 tt
b)
1 TT: 2 Tt: 1 tt
c)
2 TT: 1 Tt: 1 tt
d)
0 TT: 0 Tt: 4 tt
50.
A green pea plant (GG) is being crossed with a green pea plant (Gg). What is the phenotype?
a)
100 % rainbow 
b)
50% yellow and 50% green 
c)
100% green
d)
100% yellow 
51.
A red flower (Rr) is crossed with a white flower (rr). What is the genotype?
a)
0 RR; 0 Rr: 4 rr
b)
2 RR; 0 Rr: 2 rr
c)
4 RR; 0 Rr: 0 rr
d)
0 RR; 2 Rr: 2 rr
52.
Two brown eyed parents (Bb) have a baby. What is the chance the baby is blue eyed?
a)
0 %
b)
25%
c)
50%
d)
75%
53.
What is the probability of heterozygous offspring?
a)
25%
b)
50%
c)
0%
d)
100%
54.
What allele combination should go in the missing box?
a)
AA
b)
Aa
c)
aa
d)
none of these
55.
W=white hair
w= non-white hair
If you cross a horse with WW and a horse with ww what fraction of the offspring would be expected to have white hair?
a)
none
b)
3/4
c)
1/2
d)
all
56.
Having two of the same genes for the trait (TT, tt); Both dominant or both recessive.
a)
homozygous or purebred
b)
heterozygous or hybrid
c)
twin offspring
d)
pairs of chromosomes
57.
Which of the following alleles is homozygous (purebred) recessive?
a)
Tt
b)
tt
c)
TT
d)
t
58.
Which of the following is a phenotype?
a)
Aa
b)
red hair
c)
heterozygous genes
d)
mutated DNA
59.
Aa is
a)
homozygous (purebred)
b)
heterozygous (hybrid)
60.
G = green, g = yellow
The genotype for a yellow plant is...
a)
GG
b)
Gg
c)
gg
d)
all of the choices result in yellow
61.
T = tall an t = short
TT and Tt would result in  the following phenotype
a)
short
b)
tall
c)
medium sized
d)
neither tall or short
62.
Who is considered the "father of genetics"?
a)
Gregor Mendel
b)
Reginald Punnett
c)
James Watson
d)
Justin Bieber
63.
The scientific study of heredity is ____.
a)
Genetics
b)
Punnett squares
c)
Inheritance
d)
Biology
64.
A person heterozygous for wet earwax (Ww) mates with a person homozygous recessive for dry earwax. What is the chance their baby is heterozygous?
a)
0%
b)
25%
c)
50%
d)
100%
65.
A green pea plant (GG) is being crossed with a green pea plant (Gg). What is the phenotype?
a)
100 % rainbow 
b)
50% yellow and 50% green 
c)
100% green
d)
100% yellow 
66.
B = brown fur  b = white fur
In the punnett square, what is the probability for white fur? 
a)
0%
b)
25%
c)
50%
d)
75%
67.
In plants, tall (T) is dominant to short (t). Perform the following cross: Tt x Tt. What is the probability of producing a short plant?
a)
0%
b)
25%
c)
50%
d)
75%
68.

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

69.

In pea plants: T=tall t=short

What ratio of the offspring could be short?

a)

0 in 4

b)

1 in 4

c)

2 in 4

d)

4 in 4

70.

In a certain species of plant, the color purple (P) is dominant to the color white (p).

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

a)

25%

b)

0%

c)

100%

d)

50%

71.
What is the yellow seed genotype?
a)
aa
b)
Aa
c)
AA
d)
AA or Aa
72.
What genotype would go in box 2?
a)
BB
b)
Bb
c)
bb
73.

What is the probability of heterozygous offspring?

a)

0%

b)

100%

c)

50%

d)

25%

74.

What are the possible genotypes for this cross?

a)

TT = 25% Tt= 50% tt=25%

b)

all tall

c)

TT= 75% tt = 25%

d)

Tt = 100%

75.

What genotype would go in box 4?

a)

BB

b)

Bb

c)

bb

76.

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

a)

AA, Aa, aa

b)

AA only

c)

Aa only

d)

aa only

77.

What genotype would go in box 1?

a)

BB

b)

Bb

c)

bb

78.

What are the possible percentage of genotypes for the offspring? (A-Brown hair; a-blond hair)

a)

100% AA

b)

75% AA; 25% aa

c)

25% AA; 50% Aa; 25% aa

79.
W=white hair
w= non-white hair
If you cross a horse with WW and a horse with ww what fraction of the offspring would be expected to have white hair?
a)
none
b)
3/4
c)
1/2
d)
all
80.

What is the possibility of this offspring having the dominant trait?

a)

50%

b)

75%

c)

25%

d)

0%

81.
What is the missing allele?
a)
a
b)
A
c)
AA
d)
aa
82.

If T=tall and t=short

What is the ratio for short phenotype in this cross?

a)

0:4

b)

1:4

c)

2:4

d)

3:4