Question 1

Which of the following best describes the structure of a bacterial chromosome?

Accepted Answer

A circular, double-stranded DNA molecule associated with a small amount of protein

Question 2

What is the primary function of histones in eukaryotic cells?

Accepted Answer

To package DNA into nucleosomes, facilitating chromatin compaction

Question 3

Which of the following statements about chromatin is correct?

Accepted Answer

Chromatin consists of DNA and proteins, and its structure changes during the cell cycle

Question 4

During which phase of the cell cycle is euchromatin most prevalent, and why?

Accepted Answer

During interphase, to allow access for transcription of genetic information

Question 5

Which modification is most commonly associated with the formation of heterochromatin and gene silencing?

Accepted Answer

Histone methylation

Question 6

What is the basic repeating unit of chromatin structure in eukaryotic cells?

Accepted Answer

Nucleosome

Question 7

Which of the following best explains why centromeres and telomeres are typically found as constitutive heterochromatin?

Accepted Answer

Their repetitive DNA sequences require constant silencing and structural stability

Question 8

A mutation prevents histone acetylation in a eukaryotic cell. What is the most likely consequence?

Accepted Answer

Chromatin will remain tightly packed, reducing gene expression

Question 9

Which of the following is a correct sequence of chromatin compaction from least to most compact?

Accepted Answer

Nucleosome → 30-nm fiber → looped domain → chromatid

Question 10

Which process allows a cell to switch a region of chromatin from a transcriptionally inactive to an active state?

Accepted Answer

Histone acetylation

Question 11

A researcher observes that a certain gene is not expressed in liver cells but is expressed in nerve cells. Which chromatin state most likely explains this observation?

Accepted Answer

The gene is in heterochromatin in liver cells and euchromatin in nerve cells

Question 12

Which of the following best describes facultative heterochromatin?

Accepted Answer

It can switch between heterochromatin and euchromatin states depending on cellular needs

Question 13

Which of the following is a real-world example of the importance of chromatin remodeling?

Accepted Answer

Activation of genes during embryonic development

Question 14

If a eukaryotic cell fails to convert heterochromatin to euchromatin at a gene required for cell division, what is the most likely outcome?

Accepted Answer

The gene will remain silent, potentially blocking cell division

Question 15

Which of the following equations best represents the relationship between DNA length and compaction in a human chromosome?

Accepted Answer

$$L_{chromatid} = \frac{L_{DNA}}{1400}$$

Question 16

Which of the following best explains why eukaryotic chromosomes require more complex packaging than bacterial chromosomes?

Accepted Answer

Eukaryotic chromosomes are linear and must fit into the confined space of the nucleus

Question 17

Which of the following is a plausible consequence of a mutation that prevents the formation of constitutive heterochromatin at telomeres?

Accepted Answer

Increased risk of chromosome degradation and fusion

Question 18

Which of the following best describes the role of the nucleoid in bacterial cells?

Accepted Answer

It is the region where the bacterial chromosome is located and supercoiled

Question 19

Which of the following mechanisms is most likely to increase the accessibility of a gene for transcription?

Accepted Answer

Histone acetylation

Question 20

A scientist is studying a region of DNA that is highly repetitive and never transcribed. Which chromatin state is this region most likely to be in?

Accepted Answer

Constitutive heterochromatin

Bio 100 LEC Chapter 16 Module 3

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드