Question 1

Which of the following best describes the process of transcription in eukaryotic cells?

Accepted Answer

Transcription occurs in the nucleus and produces an mRNA molecule complementary to the DNA template.

Question 2

During translation, what is the role of the anticodon on tRNA?

Accepted Answer

It pairs with the complementary codon on mRNA to ensure the correct amino acid is added.

Question 3

A mutation changes a codon from $$	ext{GAA} to$$ $$	ext{GAG}. $$What type of mutation is this, and what is its likely effect?

Accepted Answer

Silent mutation; no change in the amino acid sequence.

Question 4

Which of the following best explains why eukaryotic mRNA undergoes splicing before translation?

Accepted Answer

To remove introns and join exons, producing a mature mRNA that codes for protein.

Question 5

If a DNA template strand reads $$5'	ext{-TACGGTACG-}3'$$, what will be the sequence of the mRNA produced during transcription?

Accepted Answer

$$5'	ext{-AUGCCAUGC-}3'$$

Question 6

Which of the following is a consequence of a frameshift mutation in a protein-coding gene?

Accepted Answer

All codons downstream of the mutation are altered, potentially resulting in a nonfunctional protein.

Question 7

A ribosome moves along an mRNA strand in which direction during translation?

Accepted Answer

From the 5' end to the 3' end.

Question 8

Which of the following best describes a missense mutation?

Accepted Answer

A mutation that changes one amino acid in the protein sequence.

Question 9

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

Accepted Answer

It protects the mRNA from degradation and assists in export from the nucleus.

Question 10

A patient has a mutation in the gene encoding hemoglobin that changes a codon from $$	ext{GAG} to$$ $$	ext{GTG}. $$What is the likely result?

Accepted Answer

A missense mutation resulting in sickle cell anemia.

Question 11

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

Accepted Answer

The genetic code is universal, with few exceptions, and is redundant.

Question 12

Which process is responsible for removing introns from pre-mRNA in eukaryotes?

Accepted Answer

Splicing

Question 13

A mutation in a gene results in a premature stop codon. What is the most likely effect on the protein product?

Accepted Answer

The protein will be truncated and likely nonfunctional.

Question 14

Which of the following is true regarding the flow of genetic information in cells?

Accepted Answer

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

Question 15

Which of the following is a real-world example of a point mutation causing a genetic disorder?

Accepted Answer

Sickle cell anemia caused by a single nucleotide substitution in the beta-globin gene.

Question 16

Which of the following best describes a nonsense mutation?

Accepted Answer

A mutation that changes a codon to a stop codon, terminating translation prematurely.

Question 17

During translation, what is the significance of the start codon $$	ext{AUG}$$?

Accepted Answer

It codes for methionine and signals the initiation of translation.

Question 18

Which of the following is a function of ribosomes during protein synthesis?

Accepted Answer

They catalyze the formation of peptide bonds between amino acids.

Question 19

A mutation in a regulatory region of a gene (such as an enhancer) can have which of the following effects?

Accepted Answer

It can alter the level of gene expression, potentially leading to disease.

Question 20

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

Accepted Answer

Multiple codons can specify the same amino acid.

Genetic Information Flow, Transcription, Translation, and Mutations: Study Notes for General Biology

Study Guide - Practice Questions