Question 1

Which of the following is NOT an essential characteristic of hereditary material as described in the study materials?

Accepted Answer

It must be mutable, undergoing a low rate of mutations that introduces genetic variation.

Question 2

Which of the following statements about the directionality of DNA synthesis is correct?

Accepted Answer

New nucleotides are added to the 3' end of the growing strand.

Question 3

Which of the following best describes the structure of B-form DNA?

Accepted Answer

Right-handed helix, 10.4 base pairs per turn, 2 nm diameter

Question 4

Which of the following forces is NOT involved in stabilizing the DNA double helix?

Accepted Answer

Covalent bonding between complementary bases

Question 5

A virus with a genome consisting of single-stranded RNA, an envelope, and a genome size of 19,000 bp is most likely:

Accepted Answer

Ebola virus

Question 6

Which of the following statements about retroviruses is TRUE?

Accepted Answer

Retroviruses contain a gene for reverse transcriptase.

Question 7

Which of the following best explains why eukaryotic genomes can be much larger than prokaryotic genomes without a proportional increase in gene number?

Accepted Answer

Eukaryotic genomes contain large amounts of repetitive and non-coding DNA.

Question 8

Which of the following repetitive DNA elements is unique to primates and makes up about 10% of the human genome?

Accepted Answer

SINEs (Alu elements)

Question 9

Which enzyme is responsible for introducing negative supercoils into bacterial DNA?

Accepted Answer

DNA gyrase (topoisomerase II)

Question 10

Which of the following best describes the packaging of eukaryotic DNA into chromosomes?

Accepted Answer

DNA is wrapped around histone octamers to form nucleosomes, which coil into a 30-nm fiber, then form radial loops attached to a protein scaffold.

Question 11

Which of the following is a function of the major groove in B-form DNA?

Accepted Answer

It provides access for proteins to recognize specific base sequences.

Question 12

Which of the following statements about bacterial genomes is FALSE?

Accepted Answer

Bacterial genomes are packaged with histone proteins.

Question 13

Which of the following best describes the difference between LINEs and SINEs?

Accepted Answer

LINEs code for reverse transcriptase, while SINEs do not.

Question 14

Which of the following is a correct description of a nucleosome?

Accepted Answer

A segment of DNA wrapped around an octamer of histone proteins.

Question 15

Which of the following is TRUE regarding the genomes of archaea?

Accepted Answer

Archaeal genomes are circular and often contain histone-like proteins.

Question 16

A scientist is analyzing a genome that is 4.5 million base pairs, circular, 90% coding, and lacks histones. This genome most likely belongs to:

Accepted Answer

A bacterium

Question 17

Which of the following best explains why negative supercoiling is more common in bacterial DNA?

Accepted Answer

It makes the DNA more compact and easier to separate for replication and transcription.

Question 18

Which of the following is a function of telomeres in eukaryotic chromosomes?

Accepted Answer

They consist of repetitive DNA sequences that protect chromosome ends.

Question 19

Which of the following best describes the difference between euchromatin and heterochromatin?

Accepted Answer

Euchromatin is less condensed and contains more actively expressed genes.

Question 20

Which of the following is TRUE about variable number tandem repeats (VNTRs)?

Accepted Answer

They are highly specific to individuals and used in DNA fingerprinting.

Chapter 6

Guida di studio - Domande di pratica

Study guide - Flashcard