Question 1

Which of the following best describes the central dogma of molecular biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

In eukaryotic cells, which of the following processes occurs in the cytoplasm?

Accepted Answer

Translation

Question 3

A mutation changes a codon from UAU (tyrosine) to UAA. What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 4

Which of the following modifications is added to the 3' end of a eukaryotic pre-mRNA during processing?

Accepted Answer

Poly-A tail

Question 5

A gene contains the following sequence on its template strand: 3'-TACGGTACC-5'. What is the corresponding mRNA sequence?

Accepted Answer

$$5'	ext{AUGCCAUGG}3'$$

Question 6

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

Accepted Answer

The code is redundant, with multiple codons specifying the same amino acid.

Question 7

During translation, which site on the ribosome does the incoming aminoacyl-tRNA first bind?

Accepted Answer

A site

Question 8

A point mutation in the gene for pigmentation in donkeys results in a nonfunctional enzyme. What is the most likely phenotypic outcome?

Accepted Answer

The donkey will have no pigment.

Question 9

Which of the following best explains why prokaryotes can begin translation before transcription is complete?

Accepted Answer

Transcription and translation both occur in the cytoplasm in prokaryotes.

Question 10

Which of the following is NOT a function of the 5' cap and poly-A tail added to eukaryotic mRNA?

Accepted Answer

Direct the splicing of introns

Question 11

A mutation causes the insertion of two nucleotides into a coding region of a gene. What is the most likely result?

Accepted Answer

A frameshift mutation

Question 12

Which enzyme is responsible for attaching the correct amino acid to its tRNA?

Accepted Answer

Aminoacyl-tRNA synthetase

Question 13

Alternative RNA splicing allows eukaryotic cells to:

Accepted Answer

Produce multiple polypeptides from a single gene

Question 14

Which of the following best describes the role of the TATA box in eukaryotic transcription?

Accepted Answer

It is a promoter element crucial for forming the initiation complex.

Question 15

If a protein is destined to be secreted from a eukaryotic cell, where is it synthesized?

Accepted Answer

On ribosomes bound to the endoplasmic reticulum

Question 16

Which of the following statements about exons and introns is correct?

Accepted Answer

Exons are joined together to form the coding sequence of mature mRNA.

Question 17

A tRNA has the anticodon 5'-UAC-3'. Which mRNA codon will it pair with, and which amino acid will it carry?

Accepted Answer

5'-AUG-3'; Methionine

Question 18

During elongation in translation, what is the correct order of tRNA movement through the ribosome?

Accepted Answer

A site → P site → E site

Question 19

Which of the following best explains why a single base-pair insertion in a gene can have a dramatic effect on the resulting protein?

Accepted Answer

It causes a frameshift, altering the reading frame of the gene.

Question 20

Which of the following is a direct result of a nonsense mutation in a gene?

Accepted Answer

A protein with a premature stop codon

Gene Expression: From Gene to Protein (Chapter 17 Study Guide)

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