wayground logo

Free Printable Worksheets

NEW

Font size

S
M
L
XL
Worksheets

Exploring DNA: Structure and Mutations

Total questions: 29

Worksheet time: 30mins

Name
Class
Date
1.

What is the shape of the DNA molecule?

a)

Linear

b)

Double helix

c)

Circular

d)

Zigzag

2.

Which of the following base pairs is correct according to the base pairing rules?

a)

Adenine - Cytosine

b)

Guanine - Thymine

c)

Adenine - Thymine

d)

Cytosine - Thymine

3.

During DNA replication, which enzyme is responsible for unwinding the DNA double helix?

a)

DNA polymerase

b)

Helicase

c)

Ligase

d)

Primase

4.

What is the role of DNA polymerase in DNA replication?

a)

Unwinds the DNA strand

b)

Joins Okazaki fragments

c)

Synthesizes new DNA strands

d)

Adds RNA primers

5.

Which of the following is a type of point mutation?

a)

Inversion

b)

Deletion

c)

Substitution

d)

Duplication

6.

What is the complementary strand for the DNA sequence 5'-ATCG-3'?

a)

5'-TAGC-3'

b)

3'-TAGC-5'

c)

5'-CGAT-3'

d)

3'-CGAT-5'

7.

Which of the following mutations is likely to have the most significant effect on a protein?

a)

Silent mutation

b)

Missense mutation

c)

Nonsense mutation

d)

Neutral mutation

8.

How does a frameshift mutation affect the reading frame of a gene?

a)

It does not affect the reading frame.

b)

It shifts the reading frame, altering the entire amino acid sequence downstream.

c)

It only affects the first codon.

d)

It replaces one amino acid with another.

9.

Predict the effect of a substitution mutation that changes a codon from UUU to UUC.

a)

It will result in a frameshift mutation.

b)

It will cause a nonsense mutation.

c)

It will have no effect on the protein (silent mutation).

d)

It will change the protein structure significantly.

10.

Analyze the impact of a deletion mutation in a gene coding for an enzyme.

a)

The enzyme will be produced normally.

b)

The enzyme will be produced but with altered function.

c)

The enzyme will not be produced at all.

d)

The enzyme will be produced with enhanced function.

11.

Evaluate the importance of proofreading by DNA polymerase during replication.

a)

It ensures the DNA is unwound properly.

b)

It prevents the formation of Okazaki fragments.

c)

It reduces the frequency of mutations by correcting errors.

d)

It adds RNA primers to the DNA strand.

12.

What is the consequence of a nonsense mutation in a gene?

a)

It results in a longer protein.

b)

It results in a shorter, nonfunctional protein.

c)

It has no effect on the protein.

d)

It changes one amino acid in the protein.

13.

Which enzyme is responsible for adding nucleotides to the growing DNA strand during replication?

a)

Helicase

b)

Ligase

c)

DNA polymerase

d)

Primase

14.

What is the effect of a silent mutation on a protein?

a)

It changes the protein's function.

b)

It has no effect on the protein's function.

c)

It results in a nonfunctional protein.

d)

It causes the protein to be longer.

15.

Which of the following best describes a missense mutation?

a)

A mutation that does not change the amino acid sequence.

b)

A mutation that results in a premature stop codon.

c)

A mutation that changes one amino acid in the protein.

d)

A mutation that shifts the reading frame.

16.

Discuss the potential effects of a frameshift mutation on protein synthesis.

a)

It may result in a protein with a completely different amino acid sequence.

b)

It will have no effect on the protein.

c)

It will only affect the first amino acid.

d)

It will result in a longer protein.

17.

How does the enzyme helicase facilitate DNA replication?

a)

It synthesizes new DNA strands.

b)

It joins Okazaki fragments.

c)

It unwinds the DNA double helix.

d)

It adds RNA primers.

18.

A segment of DNA is shown in the diagram. Which of these identifies the part of the DNA segment labeled A?

a)

Nucleotide

b)

Phosphate group

c)

Hydrogen bond

d)

Deoxyribose

19.
Name this structure
a)
double helix
b)
nucelotide
c)
twisted ladder
d)
hydrogen bond
20.
What is occurring in this picture?
a)
Translation
b)
Replication
c)
Translocation
d)
Transcription
21.

What is the purpose of transcription?

a)

To copy DNA into a molecule of mRNA.

b)

To read a copy of mRNA to build a protien.

22.
The diagram shows the process of
a)
Transcription
b)
Translation
c)
Replication
d)
Mitosis
23.

What is the purpose of the chart shown in the image?

a)

To show the structure of DNA

b)

To show the process of transcription

c)

To indicate what codon codes for each amino acid

d)

To display the different types of nucleic acids

24.

Which of the following is the start codon?

a)

UGA

b)

AUG

c)

GUA

d)

GAU

25.

A DNA mutation is a change in a DNA base sequence. This can occur if one or more extra bases are inserted or added into a DNA sequence, if one or more bases get replaced by different bases, or if one or more bases are lost or removed from a DNA sequence.

Identify the deletion mutation if the NORMAL DNA sequence was:

  T A C   A G G   G C T   C C C

a)

Mutation 1

T A C   A G G   G T T   C C C

b)

Mutation 2

T A C   G G G   C T C   C C

c)

Mutation 3

T A C   A G A   G G C   T C C   C

26.

A DNA mutation is a change in a DNA base sequence. This can occur if one or more extra bases are inserted or added into a DNA sequence, if one or more bases get replaced by different bases, or if one or more bases are lost or removed from a DNA sequence.

Identify the insertion mutation if the NORMAL DNA sequence was:

  T A C   A G G   G C T   C C C

a)

Mutation 1:

T A C T A G G G C T C C C

b)

Mutation 2:

T A G A G G G C T C C C

c)

Mutation 3:

T A G A G G C C T C C C

27.

What type of mutation involves substituting a DNA base with a different base but still forms the same protein?

a)

point mutation

b)

frameshift mutation

c)

silent mutation

d)

chromosomal mutation

28.

The change in the second codon of DNA sequence from GAA to GAG does not affect the amino acid sequence. This is an example of ........................................

a)

Nonsense mutation

b)

Missense mutation

c)

Silent Mutation

d)

Frameshift Mutation

29.

Mutations in somatic cells can be passed down to offspring.

a)

TRUE

b)

FALSE