Question 1

Which of the following best describes the flow of genetic information according to the central dogma of molecular biology?

Accepted Answer

DNA → RNA → Protein

Question 2

During transcription, which strand of DNA is used as the template for mRNA synthesis, and in which direction is the mRNA synthesized?

Accepted Answer

The template strand; 5' → 3'

Question 3

What is the primary function of a promoter sequence in a gene?

Accepted Answer

It signals where RNA polymerase should begin transcription.

Question 4

Which of the following modifications occur to eukaryotic mRNA before it leaves the nucleus?

Accepted Answer

Addition of a 5' cap, splicing of introns, and addition of a poly(A) tail

Question 5

A mutation in the promoter region of a gene is most likely to affect which aspect of gene expression?

Accepted Answer

The timing, location, or amount of transcription

Question 6

Which of the following statements about gene expression in multicellular organisms is correct?

Accepted Answer

Different cell types express different sets of genes, leading to different proteins and functions.

Question 7

During the elongation phase of transcription, which chemical bond is formed between nucleotides?

Accepted Answer

Phosphodiester bond

Question 8

Which of the following sequences is removed from the pre-mRNA during RNA processing and does not code for protein?

Accepted Answer

Introns

Question 9

If the template DNA strand has the sequence 5'-ATGCGT-3', what will be the sequence of the mRNA produced?

Accepted Answer

3'-UACGCA-5'

Question 10

Which of the following best explains why muscle cells and nerve cells in the same individual look and function differently?

Accepted Answer

They express different sets of genes.

Question 11

What is the role of transcription factors in gene expression?

Accepted Answer

They bind to promoter regions and regulate the initiation of transcription.

Question 12

Which of the following statements about the directionality of nucleic acid synthesis is correct?

Accepted Answer

Both DNA and RNA are synthesized in the 5' to 3' direction.

Question 13

Alternative splicing allows a single gene to:

Accepted Answer

Produce multiple different proteins

Question 14

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

Accepted Answer

Coding for the start amino acid

Question 15

A scientist discovers a mutation that prevents the addition of a poly(A) tail to mRNA. Which of the following is a likely consequence?

Accepted Answer

The mRNA will be less stable and degraded more quickly.

Question 16

Which of the following best describes the relationship between the coding strand of DNA and the mRNA produced during transcription?

Accepted Answer

They are identical except that mRNA has U instead of T.

Question 17

Transcription ends when RNA polymerase encounters which of the following?

Accepted Answer

A terminator sequence

Question 18

Which of the following is true regarding the use of DNA strands as templates for transcription in a chromosome?

Accepted Answer

The template strand for one gene may be the coding strand for another gene.

Question 19

A cell is observed to have a mutation in a transcription factor that prevents it from binding to the promoter. What is the most likely result?

Accepted Answer

Transcription of the gene will not occur.

Question 20

Which of the following best explains why changes in DNA sequence can lead to changes in protein function?

Accepted Answer

DNA sequence determines mRNA sequence, which determines amino acid sequence, which determines protein function.

Transcription and Gene Expression: From DNA to Protein

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