DNA Structure And Replication Quiz Challenge
DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. Test your knowledge of this topic by taking the quiz below.
- 1.
In DNA, Thymine pairs with...
- A.
Guanine
- B.
Cytosine
- C.
Adenine
- D.
Uracil
Correct Answer
C. AdenineExplanation
Remember A always pairs with T
G always pairs with C
*IN RNA, T IS SWAPPED OUT FOR URate this question:
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- 2.
A nucleotide is made up of what three things?
- A.
Adenine, Cytosine, Guanine
- B.
2 Phosphates and a base
- C.
A sugar, adenine, and thymine
- D.
A phosphate, a sugar, and a nitrogenous base
Correct Answer
D. A phosphate, a sugar, and a nitrogenous baseExplanation
A nucleotide is composed of a phosphate group, a sugar molecule, and a nitrogenous base. The phosphate group provides a negative charge and is responsible for forming the backbone of the nucleic acid chain. The sugar molecule, typically deoxyribose in DNA or ribose in RNA, provides a structural framework for the nucleotide. The nitrogenous base, which can be adenine, cytosine, guanine, or thymine (in DNA) or uracil (in RNA), is responsible for the genetic information carried by the nucleotide. Together, these three components make up the building blocks of nucleic acids.Rate this question:
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- 3.
How many bases are there in DNA?
- A.
2
- B.
3
- C.
4
- D.
5
Correct Answer
C. 4Explanation
DNA, or deoxyribonucleic acid, is composed of four different bases: adenine (A), cytosine (C), guanine (G), and thymine (T). These bases pair up in specific combinations to form the rungs of the DNA ladder. Adenine pairs with thymine, and cytosine pairs with guanine. Therefore, there are four bases in DNA.Rate this question:
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- 4.
The DNA backbone is made up of...
- A.
Phosphates
- B.
Sugars
- C.
Sugars and bases
- D.
Phosphates and sugars
Correct Answer
D. Phosphates and sugarsExplanation
The DNA backbone is made up of phosphates and sugars. Phosphates form the backbone of the DNA molecule, providing stability and strength. Sugars, specifically deoxyribose in DNA, are attached to the phosphates and form the alternating sugar-phosphate backbone. This backbone structure plays a crucial role in maintaining the integrity and stability of the DNA molecule. Bases, on the other hand, are attached to the sugars and project inward, forming the rungs of the DNA ladder.Rate this question:
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- 5.
Which of the following is true?
- A.
A&T share 3 hydrogen bonds. C&G share 2 hydrogen bonds.
- B.
A&T share 2 hydrogen bonds. C&G share 3 hydrogen bonds.
- C.
A&T share covalent. C&G share ionic.
- D.
A&T share ionic. C&G share covalent.
Correct Answer
B. A&T share 2 hydrogen bonds. C&G share 3 hydrogen bonds. -
- 6.
What enzyme joins the free floating nucleotides to the unzipped strands of DNA?
- A.
DNA polymerase
- B.
RNA polymerase
- C.
Helicase
- D.
TRNA
Correct Answer
A. DNA polymeraseExplanation
DNA polymerase is the correct answer because it is the enzyme responsible for joining the free floating nucleotides to the unzipped strands of DNA during DNA replication. This enzyme is essential for the synthesis of new DNA strands and plays a crucial role in maintaining the integrity and fidelity of the genetic information. RNA polymerase is involved in transcribing DNA into RNA, helicase is responsible for unwinding the DNA double helix, and tRNA is involved in protein synthesis.Rate this question:
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- 7.
The coding region of DNA is made up of...
- A.
Sugar
- B.
Phosphate
- C.
Base
- D.
DNA
Correct Answer
C. BaseExplanation
The coding region of DNA is made up of bases. Bases are the building blocks of DNA and they include adenine (A), cytosine (C), guanine (G), and thymine (T). These bases pair up with each other to form the double helix structure of DNA. The sequence of these bases determines the genetic information encoded in DNA, which is responsible for the synthesis of proteins and the functioning of cells.Rate this question:
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- 8.
The structure of DNA is called
- A.
RNA polymerase
- B.
Helicase
- C.
Double helix
- D.
DNA
Correct Answer
C. Double helixExplanation
The correct answer is "double helix". The structure of DNA is known as a double helix because it consists of two strands that are twisted together in a spiral shape. This structure was first proposed by James Watson and Francis Crick in 1953 based on the X-ray diffraction data collected by Rosalind Franklin. The double helix structure allows DNA to store and transmit genetic information in a stable and efficient manner.Rate this question:
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- 9.
Which of the following DNA strands is the complementary strand to: ATGCATGA
- A.
TACGTACT
- B.
UACGUACU
- C.
CATAGTAA
- D.
TAATUAUAG
Correct Answer
A. TACGTACTExplanation
The given DNA strand "ATGCATGA" contains the nucleotides A, T, G, and C. In DNA, A always pairs with T, and G always pairs with C. Therefore, the complementary strand to "ATGCATGA" would have T, A, C, and G as its nucleotides. Among the given options, the only strand that matches this pattern is "TACGTACT".Rate this question:
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- 10.
Which of the following do you know is NOT DNA replication?
- A.
A DNA strand pairing with a strand made up of A, C, G, and U
- B.
A DNA strand being unwound by helicase
- C.
DNA polymerase attaching free nucleotides to strands of DNA
- D.
A DNA strand pairing with a strand made up of A, C, G, and T
Correct Answer
A. A DNA strand pairing with a strand made up of A, C, G, and UExplanation
DNA replication is the process by which a DNA molecule is copied to produce two identical DNA molecules. During DNA replication, a DNA strand pairs with a complementary strand made up of A, C, G, and T (not U). This process is facilitated by DNA polymerase, which attaches free nucleotides to the existing strands of DNA. Helicase is responsible for unwinding the DNA double helix. Therefore, the only option that is NOT a part of DNA replication is a DNA strand pairing with a strand made up of A, C, G, and U.Rate this question:
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Mar 20, 2023Quiz Edited by
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Jan 30, 2017Quiz Created by
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