Question 1

Which of the following statements best describes the Central Dogma of molecular biology?

Accepted Answer

Genetic information flows from DNA to RNA to protein.

Question 2

In eukaryotic cells, which RNA polymerase is responsible for transcribing genes that encode ribosomal RNA (rRNA)?

Accepted Answer

RNA polymerase I

Question 3

During transcription, which strand of DNA serves as the template for RNA synthesis?

Accepted Answer

Antisense strand

Question 4

What is the main function of the 5' cap added to eukaryotic mRNA during processing?

Accepted Answer

It facilitates the export of mRNA from the nucleus and protects it from degradation.

Question 5

Which of the following best explains why all somatic cells in an organism have the same DNA but different functions?

Accepted Answer

Different cells express different sets of genes, leading to unique structure and function.

Question 6

Which of the following is NOT a function of transcription factors in eukaryotic transcription?

Accepted Answer

Catalyzing the polymerization of RNA nucleotides.

Question 7

A mutation changes the TATA box sequence in a eukaryotic gene promoter. What is the most likely consequence?

Accepted Answer

Transcription initiation will be impaired due to reduced binding of TBP.

Question 8

Which equation correctly represents the base pairing rule during transcription?

Accepted Answer

$A_{DNA} \rightarrow U_{RNA}$

Question 9

In prokaryotic cells, what is the role of the sigma factor during transcription?

Accepted Answer

It binds to the promoter and initiates transcription by recruiting RNA polymerase.

Question 10

Which of the following statements about RNA structure is correct?

Accepted Answer

RNA is single-stranded and can fold into different shapes.

Question 11

Which process occurs in eukaryotic cells but not in prokaryotic cells?

Accepted Answer

mRNA processing, including splicing and addition of a poly(A) tail.

Question 12

If a eukaryotic cell is exposed to a drug that inhibits RNA polymerase II, which type of RNA synthesis will be most affected?

Accepted Answer

mRNA synthesis

Question 13

Which of the following best describes the direction in which RNA polymerase synthesizes RNA?

Accepted Answer

$5' \rightarrow 3'$

Question 14

A scientist discovers a cell that can make proteins only when needed. Which regulatory mechanism is most likely responsible for this?

Accepted Answer

Gene expression is regulated at multiple levels, including transcription and translation.

Question 15

Which of the following is a correct statement about the promoter region of a gene?

Accepted Answer

It is located upstream of the coding region and serves as the initiation point for transcription.

Question 16

Which type of RNA is responsible for catalyzing peptide bond formation during translation?

Accepted Answer

rRNA

Question 17

A mutation prevents the addition of a poly(A) tail to eukaryotic mRNA. What is the most likely effect?

Accepted Answer

The mRNA will be less stable and degraded more quickly.

Question 18

Which of the following is a real-world example of gene expression regulation in response to environmental changes?

Accepted Answer

Bacteria increase transcription of lactose-metabolizing genes when lactose is present.

Question 19

Which of the following best explains why RNA can fold into complex shapes while DNA cannot?

Accepted Answer

RNA is single-stranded, allowing intramolecular base pairing and folding.

From DNA to Protein: Gene Expression and Transcription in Eukaryotic Cells

Study Guide - Practice Questions