Q: Which of the following best describes the flow of genetic information in a cell?

$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

Question 1

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

Accepted Answer

Helicase

Question 2

If a DNA template strand reads 3'-TACGGA-5', what is the sequence of the complementary mRNA produced during transcription?

Accepted Answer

5'-AUGCCU-3'

Question 3

Which of the following best describes the direction in which DNA polymerase III synthesizes a new DNA strand?

Accepted Answer

5' to 3' along the new strand

Question 4

Why do Okazaki fragments form on the lagging strand during DNA replication?

Accepted Answer

Because DNA polymerase can only add nucleotides to the 3' end, and the lagging strand is synthesized away from the replication fork

Question 5

Which of the following modifications is added to the 5' end of a eukaryotic pre-mRNA molecule?

Accepted Answer

5' cap (GTP)

Question 6

What is the function of the poly-A tail added to eukaryotic mRNA?

Accepted Answer

It helps the mRNA leave the nucleus, protects it from degradation, and assists ribosome binding

Question 7

Which of the following statements about the genetic code is TRUE?

Accepted Answer

The genetic code is universal to all life

Question 8

During transcription in eukaryotes, what is the role of the TATA box?

Accepted Answer

It is a promoter region that helps RNA polymerase bind to DNA

Question 9

A mutation changes a codon from UCA to UAA in an mRNA sequence. What is the most likely result?

Accepted Answer

Translation will terminate prematurely

Question 10

Which of the following best describes the relationship between the template DNA strand and the mRNA transcript?

Accepted Answer

They are complementary and antiparallel

Question 11

If the percentage of cytosine in a DNA molecule is 22%, what is the percentage of adenine?

Accepted Answer

$$28\%$$

Question 12

Which process removes introns from pre-mRNA in eukaryotes?

Accepted Answer

RNA splicing

Question 13

Which of the following is a function of proteins in the cell?

Accepted Answer

Catalyzing chemical reactions

Question 14

Which enzyme synthesizes the RNA primer during DNA replication?

Accepted Answer

Primase

Question 15

What is the start codon for translation in all organisms?

Accepted Answer

AUG

Question 16

Which of the following best explains why the genetic code is described as 'redundant'?

Accepted Answer

Some amino acids are coded by more than one codon

Question 17

A scientist isolates a nucleic acid with the following characteristics: single-stranded, contains uracil, and has a ribose sugar. What type of molecule is this?

Accepted Answer

mRNA

Question 18

Which of the following is NOT a function of the 5' cap added to eukaryotic mRNA?

Accepted Answer

Coding for an amino acid

Question 19

During translation, what is the role of tRNA?

Accepted Answer

It carries amino acids to the ribosome and matches them to the mRNA codon

Question 20

Which of the following best describes the flow of genetic information in a cell?

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Gene Expression: DNA Structure, Replication, Transcription, and Translation

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