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Genetics Review

Total questions: 50

Worksheet time: 50mins

Name
Class
Date
1.

Heterozygous means ________________.

a)
the alleles are the same
b)
the alleles are different
c)
the alleles are absent
d)
the alleles are present
2.

G = green, g = yellow
The genotype for a yellow plant is ______.

a)
GG
b)
Gg
c)
gg
3.
Which of the following alleles is homozygous (purebred) recessive?
a)
Tt
b)
tt
c)
TT
4.
Aa, DD, bB, yy are all examples of
a)
genotypes
b)
phenotypes
5.
Which of the following genotypes is homozygous dominant?
a)
Aa
b)
AA
c)
aa
6.
Which of the following genotypes is heterozygous?
a)
Bb
b)
BB
c)
bb
7.
In a flowering plant species, red flower color (R) is dominant over white flower color (r). What is the genotype of any red-flowering plant resulting from this species?
a)

RR or rr

b)
RR or Rr
8.
What you see, or the physical appearance.
a)
Genotype
b)
Phenotype
c)
Homozygous
d)
Heterozygous
9.
Which of the following is a phenotype?
a)
Aa
b)
red hair
c)
heterozygous
d)
DNA
10.
One form of a gene is called_______________
a)

DNA

b)

a phenotype

c)
a trait
d)
an allele
11.

In this Punnett Square, which is the dominant trait?
The B stands for bud.

a)
purple flower bud
b)
white flower bud
12.

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
13.

Which of the following alleles is homozygous recessive?

a)
Tt
b)
tt
c)
TT
14.

T - tall and t = short
In the Punnett Square below, what belongs in the missing square

a)
tt
b)
Tt
c)
TT
15.

Which of the following is homozygous dominant?

a)
Yy
b)
yy
c)
YY
16.

In a Punnett square each box represents the probability of a(n) _______ trait.

a)

offspring's

b)

parent's

17.

A diagram that shows all the possible combinations of alleles that can result from a genetic cross

a)
Gene
b)
Pedigree
c)
Punnett Square
d)
Dominant
18.
Heredity is the passing of traits from _____________________ to _____________________
a)
predators to prey
b)
water to rain
c)
parents to offspring
d)
fungi to protists
19.

________ is the study of how traits are passed on from generation to generation, or inherited.

a)

Dominant traits

b)

Ratio

c)

Phenotype

d)

Genetics

20.

Brown hair is an example of which of the following?

a)

Genotype

b)

Phenotype

21.
What does the prefix hetero- in heterozygous mean?
a)
same
b)
different
c)
dating
d)
human
22.

The physical appearance of a trait is known as the_________.

a)
genotype
b)
phenotype
23.

The different forms of a gene are called _________.

a)
traits
b)
chromosomes
c)
alleles
d)
peas
24.

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

25.

Which genotype below best fits in box 2?

a)
BB
b)
Bb
c)
bb
26.

What is the probability of heterozygous offspring?

a)

0%

b)

100%

c)

50%

d)

25%

27.

Who studied different characteristics of pea plants by cross-pollinating plants?

a)

Gregor Mendel

b)

Albert Punnett

c)

Sir Isaac Newton

d)

David Kuster

28.

If a homozygous black cat (BB) is crossed with a homozygous white cat (bb), what is the probability of having a cat with white fur?

a)

100%

b)

0%

c)

75%

d)

25%

29.

What does RR mean?

a)

two dominant alleles

b)

heterozygous alleles

c)

one dominant and one recessive allele

30.

Genotype or Phenotype: Freckles

a)

Genotype

b)

Phenotype

31.

Genotype or Phenotype: ff

a)

Genotype

b)

Phenotype

32.

Homozygous or Heterozygous: ff

a)

Homozygous

b)

Heterozygous

33.

Homozygous or Heterozygous: Ff

a)

Homozygous

b)

Heterozygous

34.

What is a trait that shows only if both parents pass it on?

a)

recessive

b)

dominant

35.

Which of the following genotypes is homozygous (purebred) recessive?

a)
Tt
b)
tt
c)
TT
36.

An allele that only needs one copy to produce its trait is called _______.

a)
Dominant
b)
Recessive
37.

An allele that needs 2 copies to produce its trait is called ________.

a)
Dominant
b)
Recessive
38.

Hereditary material with the instructions to make an organism is called ________.

a)

DNA

b)

phenotype

c)

heterozygous

39.

What percentage of the possible offspring will be heterozygous?

a)
25%
b)
50%
c)
75%
d)
100%
40.
What percentage of the offspring will be heterozygous dominant?
a)
100%
b)
75%
c)
50%
d)
25%
41.
If two purebred species (BB) are crossed, what percentage of their offspring would be BB?
a)
25%
b)
50%
c)
75%
d)
100%
42.
Round (R) seeds are dominant to wrinkled (r) seeds.
What is the genotype for a homozygous dominant offspring?
a)
RR
b)
Rr
c)
rr
43.
What is the percentage of a homozyogus dominant offspring?
a)
75%
b)
50%
c)
25%
d)
0%
44.
D = dimples        d = no dimples 
What is the genotype for a homozygous recessive offspring?
a)
DD
b)
Dd
c)
dd
45.
What percentage of the offspring will be purebred dominant?
a)
0%
b)
25%
c)
50%
d)
75%
46.
In Mendel's pea plants, the homozygous recessive phenotype was white flowers.  If Mendel crossed two homozygous recessive pea plants, what color flowers would be seen in the offspring?
a)
white 
b)
purple
47.
What is the percentage of homozygous recessive offspring?
a)
0%
b)
25%
c)
50%
d)
75%
48.

What is a section of DNA containing instructions for making a specific protein?

a)

chromosome

b)
gene
c)
dominant trait
d)
nucleus
49.

Which of the following is NOT an example of a trait?

a)

eye color

b)

ear shape

c)

 species

d)

body height

50.
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%