Question 1

Which of the following best describes an 'interrupted gene' in eukaryotes?

Accepted Answer

A gene in which the coding sequence is not continuous due to the presence of introns.

Question 2

During the transcription of a eukaryotic gene, which of the following sequences are present in the primary RNA transcript but not in the mature mRNA?

Accepted Answer

Introns

Question 3

A mutation in the promoter region of a gene most likely results in which of the following outcomes?

Accepted Answer

Altered levels of gene expression, potentially leading to loss or gain of function.

Question 4

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

Accepted Answer

Exons are coding sequences that remain in mature mRNA, while introns are non-coding sequences removed during splicing.

Question 5

Which of the following best explains why introns evolve more rapidly than exons?

Accepted Answer

Introns lack selective pressure to produce a functional polypeptide, allowing more sequence variation.

Question 6

A gene contains the following regions: promoter, 5' UTR, exons, introns, and 3' UTR. Which regions are present in the mature mRNA after processing?

Accepted Answer

5' UTR, exons, and 3' UTR

Question 7

Which of the following is a possible consequence of alternative splicing?

Accepted Answer

Production of multiple related or unrelated proteins from a single gene

Question 8

In eukaryotic transcription, what is the correct order of events?

Accepted Answer

Transcription initiation, RNA synthesis, splicing, and then formation of mature mRNA

Question 9

Which of the following best describes an open reading frame (ORF)?

Accepted Answer

A sequence of DNA or RNA that contains a start codon, a series of codons, and a stop codon, potentially encoding a protein.

Question 10

How many possible reading frames exist in a single-stranded mRNA molecule?

Accepted Answer

$$3$$

Question 11

Which of the following is TRUE regarding the organization of interrupted genes across different organisms?

Accepted Answer

The positions of introns are usually conserved, but their lengths can vary greatly.

Question 12

A mutation that causes a loss of function (LOF) in a regulatory site of a gene would most likely result in:

Accepted Answer

No or little protein being produced from the gene.

Question 13

Which of the following statements about prokaryotic and eukaryotic genes is correct?

Accepted Answer

Prokaryotic genes are usually colinear and lack introns.

Question 14

Which of the following best explains why alternative splicing can result in unrelated proteins from the same gene?

Accepted Answer

Alternative splicing can change the reading frame, resulting in different amino acid sequences.

Question 15

If a DNA sequence is transferred horizontally from another species and lands in an intron, what is the most likely outcome?

Accepted Answer

It may be inherited vertically through generations without affecting protein coding.

Question 16

Which of the following is a typical size for an exon in terms of the number of amino acids it encodes?

Accepted Answer

$$30-60$$ amino acids

Question 17

Which of the following is NOT a component of the mature eukaryotic mRNA?

Accepted Answer

Introns

Question 18

Which of the following best describes the relationship between exons and protein domains?

Accepted Answer

Exons can correspond to protein domains, which are subfunctions of proteins that fold independently.

Question 19

A gene is defined as a transcription unit. Which of the following is TRUE about this definition?

Accepted Answer

A gene includes both coding and regulatory (promoter) regions.

Question 20

Which of the following is the correct direction for RNA polymerase reading the template strand during transcription?

Accepted Answer

3' to 5'

The Interrupted Gene: Structure, Function, and Variation in Eukaryotic Genomes

Guida di studio - Domande di pratica