Question 1

A human somatic cell contains 46 chromosomes. After DNA replication during the S phase, how many chromatids are present in the cell?

Accepted Answer

92

Question 2

Which of the following best describes the role of cyclin-dependent kinases (CDKs) in the cell cycle?

Accepted Answer

They regulate cell cycle progression by phosphorylating target proteins when bound to cyclins.

Question 3

During which phase of meiosis does crossing over occur, and what is its significance?

Accepted Answer

Prophase I; it increases genetic variation among gametes.

Question 4

A cell is observed to lack density-dependent inhibition and anchorage dependence. What is the most likely identity of this cell?

Accepted Answer

A cancer cell

Question 5

If a cell fails to pass the G1 checkpoint due to DNA damage, what is the most likely outcome?

Accepted Answer

The cell will repair the DNA or enter G0 phase.

Question 6

Which of the following best explains independent assortment during meiosis?

Accepted Answer

Homologous chromosomes align and separate independently during metaphase I.

Question 7

A diploid organism has a mutation causing nondisjunction during meiosis II. Which of the following is a possible outcome in the gametes?

Accepted Answer

Some gametes have an extra chromosome, some are missing one.

Question 8

Which of the following statements about homologous chromosomes is correct?

Accepted Answer

They carry the same genes but may have different alleles.

Question 9

Which equation correctly represents the DNA content in a cell after meiosis II, if the original cell was diploid with $$2n$$ chromosomes?

Accepted Answer

$$n$$ chromosomes per cell

Question 10

Which of the following best describes the function of tubulin during cell division?

Accepted Answer

It forms microtubules that make up the mitotic spindle.

Question 11

A researcher observes a cell with chromosomes aligned in pairs at the metaphase plate. Which process is most likely occurring?

Accepted Answer

Meiosis I metaphase

Question 12

Which of the following is a key difference between cells produced by mitosis and those produced by meiosis?

Accepted Answer

Mitosis produces genetically identical cells; meiosis produces genetically diverse cells.

Question 13

Which of the following is an advantage of sexual reproduction over asexual reproduction?

Accepted Answer

It increases genetic variation, enhancing adaptability.

Question 14

Which of the following best describes the alternation of generations?

Accepted Answer

A life cycle in which organisms alternate between haploid and diploid multicellular stages.

Question 15

Which of the following events increases genetic variation during sexual reproduction?

Accepted Answer

Crossing over during prophase I

Question 16

If a cell with 8 chromosomes undergoes mitosis, how many chromosomes will each daughter cell have?

Accepted Answer

8

Question 17

Which of the following best explains why cancer cells can form tumors?

Accepted Answer

They exhibit uncontrolled cell division due to loss of cell cycle regulation.

Question 18

Which of the following is true regarding the segregation of alleles during meiosis?

Accepted Answer

Alleles for a gene separate during meiosis I, resulting in gametes with one allele per gene.

Question 19

Which of the following best describes the role of cohesin proteins during cell division?

Accepted Answer

They hold sister chromatids together until anaphase.

Question 20

Which of the following is a characteristic of binary fission but not mitosis?

Accepted Answer

It occurs in prokaryotes.

Cell Cycle, Mitosis, Meiosis, and Genetic Variation: Study Guide

Study Guide - Practice Questions