DNA Structure and Function: Comprehensive Quizzes for University Students

Question 1

The strands of DNA are oriented antiparallel, which means that:

Accepted Answer

The 5' end of one strand faces the 3' end of the other strand.

Answer

The 3' end of one strand faces the 3' end of the other strand.

Answer

The 5' end of one strand faces the 5' end of the other strand.

Answer

The 3' end of one strand faces the 5' end of the other strand.

Question 2

Which force is primarily responsible for stabilizing the double helix structure of DNA?

Accepted Answer

Hydrogen bonds

Answer

Covalent bonds

Answer

Ionic bonds

Answer

Van der Waals forces

Question 3

Which process is considered semi-conservative?

Accepted Answer

DNA replication

Answer

Protein synthesis

Answer

Cell division

Answer

Photosynthesis

Question 4

Which of the following is NOT a function of DNA?

Accepted Answer

Synthesizing carbohydrates

Answer

Storing genetic information

Answer

Transmitting genetic information

Answer

Directing protein synthesis

Question 5

Which of the following is NOT a component of a nucleotide in DNA?

Accepted Answer

Ribose sugar

Answer

Phosphate group

Answer

Deoxyribose sugar

Answer

Nitrogenous base

Question 6

Identify the complementary strand for the following DNA sequence: 5'-ACTGT-3'.

Accepted Answer

3'-TGACA-5'

Answer

3'-UGACA-5'

Answer

5'-TGACA-3'

Answer

5'-UGACA-3'

Question 7

What type of chemical bond connects adjacent nucleotides in a DNA molecule?

Accepted Answer

Covalent bond

Answer

Hydrogen bond

Answer

Ionic bond

Answer

Peptide bond

Question 8

Which structure is formed by the interaction of DNA with histone proteins?

Accepted Answer

Nucleosome

Answer

Chromosome

Answer

Histone

Answer

Telomere

Question 9

What is the primary role of DNA methylation in regulating gene expression?

Accepted Answer

Inhibits gene expression

Answer

Activates gene expression

Answer

Modifies RNA structure

Answer

Alters DNA sequence

Question 10

Which technique is commonly used to amplify specific DNA fragments?

Accepted Answer

PCR

Answer

Electrophoresis

Answer

DNA sequencing

Answer

Southern blotting

Question 11

What is the significant impact of the discovery of the double helix structure of DNA?

Accepted Answer

Laid the foundation for understanding genetic inheritance

Answer

Led to the development of gene editing technologies

Answer

Improved medical treatments for genetic disorders

Answer

Revolutionized the field of computer science

Question 12

What is the primary function of telomeres located at the ends of chromosomes?

Accepted Answer

Protect chromosomes from degradation

Answer

Facilitate DNA replication

Answer

Control gene expression

Answer

Repair damaged DNA

Question 13

Which of the following is **not** a nitrogenous base found in DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Cytosine

Answer

Guanine

Question 14

Which of the following accurately describes the shape of the DNA molecule?

Accepted Answer

Double helix

Answer

Single helix

Answer

Circular

Answer

Linear

Question 15

Who is credited with discovering the double helix structure of DNA?

Accepted Answer

James Watson and Francis Crick

Answer

Charles Darwin

Answer

Gregor Mendel

Answer

Rosalind Franklin

Question 16

Which of the following correctly describes the complementary base pairing rule in DNA?

Accepted Answer

A pairs with T, C pairs with G

Answer

A pairs with C, T pairs with G

Answer

A pairs with G, T pairs with C

Answer

C pairs with T, G pairs with A

Question 17

Which component of the DNA molecule is responsible for storing genetic information?

Accepted Answer

Nitrogenous bases

Answer

Sugar-phosphate backbone

Answer

Hydrogen bonds

Answer

Double helix structure

Question 18

Which of the following is **not** a function of DNA?

Accepted Answer

Synthesizing proteins

Answer

Storing genetic information

Answer

Transmitting genetic information

Answer

Regulating gene expression

Question 19

Which process is responsible for making an identical copy of DNA?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 20

What is the primary function of telomeres in DNA?

Accepted Answer

Protecting chromosome ends from degradation

Answer

Regulating gene expression

Answer

Initiating DNA replication

Answer

Storing genetic information

Question 21

Which component is NOT found in a nucleotide?

Accepted Answer

Amino acid

Answer

Ribose or deoxyribose

Answer

Phosphate group

Question 22

Which nitrogenous base in the DNA double helix pairs with thymine via hydrogen bonding?

Accepted Answer

Adenine

Answer

Cytosine

Answer

Guanine

Answer

Uracil

Question 23

What type of hydrogen bonds form between complementary base pairs in the DNA double helix?

Accepted Answer

Watson-Crick bonds

Answer

Phosphodiester bonds

Answer

Glycosidic bonds

Answer

Peptide bonds

Question 24

What is the process by which DNA makes an identical copy of itself during cell division?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 25

Which enzyme is responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Answer

DNA polymerase

Answer

RNA polymerase

Answer

Ligase

Question 26

What is the primary function of telomeres in DNA structure?

Accepted Answer

Preventing the loss of genetic information during cell division

Answer

Regulating gene expression

Answer

Facilitating DNA replication

Answer

Providing structural support to the chromosome

Question 27

Which technique is commonly used to separate DNA fragments based on their size?

Accepted Answer

Gel electrophoresis

Answer

Polymerase chain reaction

Answer

DNA sequencing

Answer

Karyotyping

Question 28

Which factor does NOT influence the efficiency of DNA replication?

Accepted Answer

Sunlight

Answer

Temperature

Answer

pH

Answer

Enzyme concentration

Question 29

What is the key role of transcription in gene expression?

Accepted Answer

Creating a messenger RNA molecule that carries genetic information.

Answer

Translating the genetic code into proteins.

Answer

Replicating the DNA molecule.

Answer

Regulating gene activity.

Question 30

Which nitrogenous base is absent from DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Cytosine

Answer

Guanine

Question 31

What is the name of the helical structure formed by the two DNA strands?

Accepted Answer

Antiparallel double helix

Answer

Parallel double helix

Answer

Watson-Crick helix

Answer

Base helix

Question 32

What is the primary function of DNA?

Accepted Answer

To store and transmit genetic information

Answer

To regulate protein synthesis

Answer

To provide energy for cellular processes

Answer

To facilitate cell division

Question 33

Which type of bond links adjacent nucleotides in a DNA strand?

Accepted Answer

Glycosidic bond

Answer

Covalent bond

Answer

Hydrogen bond

Answer

Ionic bond

Question 34

Which of the following best describes the significance of the hydrogen bonds between base pairs in DNA?

Accepted Answer

They maintain the stability of the double helix.

Answer

They determine the sequence of amino acids in proteins.

Answer

They allow for the copying of genetic information.

Answer

They provide energy for DNA replication.

Question 35

What is the process by which DNA is copied into complementary strands called?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 36

Which nitrogenous base is not found in DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Thymine

Answer

Guanine

Question 37

What type of bonds form between the nitrogenous bases in a DNA molecule?

Accepted Answer

Hydrogen bonds

Answer

Covalent bonds

Answer

Ionic bonds

Answer

Van der Waals forces

Question 38

Which scientist is not known for their contributions to the discovery of the structure of DNA?

Accepted Answer

Albert Einstein

Answer

James Watson

Answer

Francis Crick

Answer

Rosalind Franklin

Question 39

Which of the following is the complementary base pairing rule that governs the formation of the DNA double helix?

Accepted Answer

G-C, A-T

Answer

A-G, C-T

Answer

A-C, G-T

Answer

C-G, A-U

Question 40

Which region of DNA is non-coding?

Accepted Answer

Introns

Answer

Exons

Answer

Promoters

Answer

Operons

Question 41

What is helicase's function in DNA replication?

Accepted Answer

To unwind the DNA double helix

Answer

To synthesize new DNA strands

Answer

To proofread newly synthesized DNA

Answer

To repair damaged DNA

Question 42

What is the final product of protein synthesis?

Accepted Answer

Polypeptides

Answer

RNA

Answer

Amino acids

Answer

Monosaccharides

Question 43

Which technique separates DNA fragments based on size?

Accepted Answer

Gel electrophoresis

Answer

PCR

Answer

DNA sequencing

Answer

DNA hybridization

Question 44

What is the role of RNA polymerase in transcription?

Accepted Answer

To synthesize a complementary RNA strand using a DNA template

Answer

To unwind the DNA double helix

Answer

To proofread newly synthesized RNA

Answer

To bind to specific sequences on DNA

Question 45

The sugar-phosphate backbone of DNA is formed by the repeating units of:

Accepted Answer

Deoxyribose and phosphate

Answer

Ribose and phosphate

Answer

Deoxyribose and nitrogenous bases

Answer

Ribose and nitrogenous bases

Question 46

Which of the following describes the shape of DNA?

Accepted Answer

Double helix

Answer

Single helix

Answer

Triple helix

Answer

Quadruple helix

Question 47

The hydrogen bonds between nitrogenous bases are responsible for:

Accepted Answer

Maintaining the double helix structure

Answer

Replicating DNA

Answer

Storing genetic information

Answer

Transcribing DNA

Question 48

Which of the following enzymes is responsible for replicating DNA?

Accepted Answer

DNA polymerase

Answer

Helicase

Answer

RNA polymerase

Answer

Ligase

Question 49

The process by which genetic information is passed from DNA to messenger RNA is called:

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Mutation

Question 50

Restriction enzymes are used in genetic engineering to:

Accepted Answer

Cut DNA at specific sequences

Answer

Repair damaged DNA

Answer

Replicate DNA

Answer

Transcribe DNA

Question 51

DNA sequencing involves determining:

Accepted Answer

The order of nitrogenous bases in DNA

Answer

The shape of DNA

Answer

The number of genes in DNA

Answer

The function of DNA

Question 52

Which type of chemical bond forms between complementary base pairs in DNA?

Accepted Answer

Hydrogen bond

Answer

Covalent bond

Answer

Ionic bond

Answer

Disulfide bond

Question 53

Which of the following is NOT a primary function of DNA?

Accepted Answer

Synthesizing proteins

Answer

Storing genetic information

Answer

Transmitting genetic information

Answer

Regulating gene expression

Question 54

The shape of a DNA molecule is described as a:

Accepted Answer

Double helix

Answer

Single helix

Answer

Triple helix

Answer

Quadruple helix

Question 55

During DNA replication, which enzyme is responsible for synthesizing new DNA strands?

Accepted Answer

DNA polymerase

Answer

Helicase

Answer

Ligase

Answer

Primase

Question 56

Which technique separates DNA fragments based on size?

Accepted Answer

Gel electrophoresis

Answer

PCR

Answer

DNA sequencing

Answer

Southern blotting

Question 57

Which of the following is NOT a nitrogenous base found in DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Thymine

Answer

Cytosine

Question 58

What type of bond holds together the two strands of the DNA double helix?

Accepted Answer

Hydrogen bond

Answer

Ionic bond

Answer

Covalent bond

Answer

Van der Waals interaction

Question 59

What is the process by which DNA is copied during cell division?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Answer

Mutation

Question 60

Which of the following technologies is used to amplify specific DNA sequences?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

DNA sequencing

Answer

Gel electrophoresis

Answer

Microarrays

Question 61

Which of the following correctly describes the base pairing rules in DNA?

Accepted Answer

Adenine pairs with thymine, and cytosine pairs with guanine.

Answer

Adenine pairs with cytosine, and thymine pairs with guanine.

Answer

Guanine pairs with cytosine, and adenine pairs with thymine.

Answer

Guanine pairs with thymine, and cytosine pairs with adenine.

Question 62

What is the typical shape of a DNA molecule?

Accepted Answer

Double helix

Answer

Single helix

Answer

Triple helix

Answer

Quadruple helix

Question 63

Which type of bond primarily maintains the double helix structure of DNA?

Accepted Answer

Hydrogen bonds

Answer

Covalent bonds

Answer

Ionic bonds

Answer

Van der Waals forces

Question 64

Which nitrogenous base is unique to DNA and not found in RNA?

Accepted Answer

Thymine

Answer

Adenine

Answer

Cytosine

Answer

Uracil