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DNA, Genetics, and Heredity Practice Test

Total questions: 55

Worksheet time: 39mins

Name
Class
Date
1.

EACH parent parent donates how many alleles to an offspring for each trait?

a)

1

b)

2

c)

3

d)

4

2.

What does homozygous mean?

a)

Having two different alleles for a particular gene.

b)

Having two identical alleles for a particular gene.

c)

An organism’s physical appearance, or visible traits.

d)

An allele that is hidden whenever the dominant allele is present.

3.

"Eye Color" as a heading would be a ?

a)

Characteristic

b)

Heterozygous

c)

Phenotype

d)

Homozygous

4.

How many total chromosomes do humans generally have?

a)

46

b)

23

c)

64

d)

2

5.

On a pedigree chart males are represented by ______.

a)

Squares

b)

Circles

6.

In a heterozygous genotype with complete dominance, the ___________ allele takes over in the phenotype.

a)

recessive

b)

dominant

c)

lower case letter

d)

both 

7.

Where do the factors for a trait come from?

a)

unrelated organisms

b)

siblings

c)

parent organisms

d)

offspring

8.

The traits that we can see, or the physical appearance.

a)
Genotype
b)
Phenotype
c)
Homozygous
d)
Heterozygous
9.

The passing of physical characteristics from parents to offspring is

a)

Trait

b)

Allele

c)

Heredity

d)

Genetics

10.

In a Punnett square, a lower case letter stands for a ____________ allele.

a)

dominant

b)

recessive

c)

homozygous

d)

heterozygous

11.

Hair color, height, eye color and freckles are examples of human traits. What do we call the physical expression of the genetic material of an organism?

a)

genetics

b)

heredity

c)

genotype

d)

phenotype

12.

Heterozygous is when...

a)

the alleles are the same, example TT

b)

the alleles are different, one recessive and one dominant, example Tt

c)

the alleles are absent, No allele

d)

the alleles are present, but are both recessive, example tt

13.

T = tall and t = short

In the punnett square shown, what belongs in the missing square

a)

tt

b)

Tt

c)

Bb

d)

TT

14.

Which of the following alleles is homozygous recessive?

a)

Tt

b)

tt

c)

TT

d)

t

15.
What ratio of the offspring from the cross shown will be homozygous recessive for the trait of tallness? 
a)

0%

b)

25%

c)

50%

d)

100%

16.

Which of the following genotypes is homozygous dominant?

a)

A

b)

Aa

c)

AA

d)

aa

17.

Which of the following genotypes is heterozygous?

a)

Bb

b)

BB

c)

bb

d)

B

18.

A recessive allele is represented by a ______ letter.

a)

lower-case

b)

capital

19.

The person who discovered the rule of heredity with his experiments with pea plants.

a)

Nelson Mandela

b)

Gregor Mendel

c)

Isaac Newton

d)

Harold Washington

20.

If you crossed a PP (purple) with a pp (white), what would the phenotypes be (assuming complete dominance)?

a)

all white

b)

all tall

c)

all purple

d)

1/2 white, 1/2 purple

21.

_________________ describes a trait that is covered over, or masked by another form of that trait.

a)

dominant

b)

punnett

c)

recessive

d)

gene

22.

The letters representing the phenotype is called

a)

phenotype

b)

genotype

23.

Different forms of the same gene are called

a)

alleles

b)

traits

24.

A ______________ square is a model that helps make genetic predictions.

a)

Punnett

b)

Mendel

25.

In a pedigree, what do circles represent?

a)

males

b)

females

c)

carrier

d)

non carrier

26.

An allele combination of two lower case letters.

a)

heterozygous

b)

homozygous dominant

c)

homozygous recessive

d)

heterozygous recessive

27.

Dominant alleles are represented by this type of letter.

a)

vowel

b)

capital letter

c)

lower case letter

d)

vowel

28.

The percentage that describes how likely something may occur.

a)

ratio

b)

probability

c)

variable

d)

exponent

29.

Another term for the genes inherited from mother and father.

a)

jeans

b)

genes

c)

DNA

d)

allele

30.

Any change in someone's DNA.

a)

deletion

b)

mutation

c)

manipulation

d)

creation

31.

According to the Punnett Square, what is the percent probability that the parents will have heterozygous children.

a)

100%

b)

50%

c)

25%

d)

0%

32.

A= Long Lashes

a= Short Lashes

According to the Punnett Square, what is the probability that the offspring will have have long lashes?

a)

100%

b)

75%

c)

50%

d)

25%

33.

What does DNA determine?

a)

traits of living things

b)

traits of nonliving things

c)

organization of living things

d)

Did Not Attempt

34.

What are the 3 parts of a nucleotide?

a)

sugar

b)

nucleo

c)

nitrogenous base

d)

phosphate group

35.

Adenine always pairs with...

a)

thymine

b)

cytosine

c)

guanine

d)

adenine

36.

Cytosine always pairs with...

a)

thymine

b)

cytosine

c)

guanine

d)

adenine

37.

Thymine always pairs with...

a)

thymine

b)

cytosine

c)

guanine

d)

adenine

38.

Guanine always pairs with...

a)

thymine

b)

cytosine

c)

guanine

d)

adenine

39.

What is the shape of DNA?

a)

double helix

b)

single helix

c)

squiggle

d)

twisty step looking thing

40.
What are the nucleotides made of?
a)
Sugar, Phosphate, nitrogen base
b)
Phosphate, Adenine, nitrogen base
c)
Thymine, Adenine, Cytomine
d)
Phosphate, Nitrogen, Adenine
41.
Why is DNA important?
a)
it is very small and very complicated
b)
it's in everything
c)
it serves as the blueprint for traits of all living things
d)
because we eat it every day for energy
42.
What are the 4 nitrogen bases?
a)
adenine, thymine, cytoplasm, and guanine
b)
adenine, thymine cytosine, and guanine
c)
adenine, thymine, cytosine, and gylcerol
d)
adenine, thymine, cytosine, and glucose
43.
Which 2 molecules forms the sides (backbone) of the DNA ladder?
a)
deoxyribose and adenine
b)
deoxyribose and a hydrogen bond
c)
sugar and the nucleus
d)
deoxyribose (sugar) and phosphate
44.
What does DNA stand for?
a)
Deoxyribonucleic acid
b)
Denitrogenous acid
c)
Deribonucleic acid
d)
Diribonucleic acid
45.

The passing of physical characteristics, or traits, from parent to offspring.

a)

Genetics

b)

Dominant allele

c)

Heredity

d)

Recessive allele

46.

The scientific study of heredity.

a)

Genetics

b)

Heredity

c)

Probability

d)

Pedigree

47.

An organism that is the offspring of many generations that show the same form of a trait.

a)

Heterozygous

b)

Dominant allele

c)

Purebred

d)

Genotype

48.

A trait that always shows up when the allele is present.

a)

Genotype

b)

Phenotype

c)

allele

d)

Dominant allele

49.

A trait that is always hidden when the dominant allele is present.

a)

Phenotype

b)

Recessive allele

c)

Genotype

d)

Heredity

50.

A chart that shows all the possible ways alleles can combine in a genetic cross.

a)

Pedigree

b)

Family tree

c)

Heterozygous

d)

Punnett square

51.

A chart or a family tree that shows the presence or absence of a trait according to the relationships within a family across several generations.

a)

Punnett square

b)

Pedigree

c)

Heredity

d)

Purebred

52.

An organism that has two identical alleles for a trait.

a)

Twins

b)

Heterozygous

c)

Phenotype

d)

Homozygous

53.

An organism that has two different alleles for a trait.

a)

Homozygous

b)

Heterozygous

c)

Dominant allele

d)

Hybrid

54.

This codominant punett square shows the genotypes of two cows and their fur color. Please select the probability of each phenotype color offspring.

B = black W = white

The probability of an all black offspring is ​ (a)  

The probability of an all white offspring is ​ (b)  

The probability of a black and white offspring is ​ (c)   5

Choose from the below words
50%
0%
25%
100%
55.

In this pedigree, some of the family members have hemaphilia. There are ​ (a)   female(s) and ​ (b)   male(s) with hemaphelia. However, there are ​ (c)   family member who carry the trait for hemaphelia.

Choose from the below words
2
1
7
3