Question 1

Which of the following best describes the main purpose of the S phase in the cell cycle?

Accepted Answer

To replicate the cell's DNA, ensuring each daughter cell receives a complete genome

Question 2

During which checkpoint does the cell verify that all DNA has been accurately replicated before proceeding to mitosis?

Accepted Answer

$$G_2$$ checkpoint

Question 3

A mutation causes a cell to bypass the M checkpoint. What is the most likely consequence?

Accepted Answer

Chromosomes may not align properly, leading to unequal distribution of genetic material

Question 4

Which of the following events occurs during anaphase of mitosis?

Accepted Answer

Sister chromatids are pulled apart toward opposite poles

Question 5

If a human somatic cell (2n = 46) completes mitosis, how many chromosomes will each daughter cell contain?

Accepted Answer

$$46$$

Question 6

Which of the following best explains why DNA replication is described as 'semiconservative'?

Accepted Answer

Each new DNA molecule consists of one parental strand and one newly synthesized strand

Question 7

A scientist observes a cell with chromosomes lined up at the center of the cell, attached to spindle fibers. Which phase is this cell in?

Accepted Answer

Metaphase

Question 8

Which of the following is NOT a function of mitosis in multicellular organisms?

Accepted Answer

Production of gametes

Question 9

What is the role of the centromere during mitosis?

Accepted Answer

It holds sister chromatids together until they are separated during anaphase

Question 10

Which of the following statements about homologous chromosomes is TRUE?

Accepted Answer

They carry the same genes but may have different alleles

Question 11

A cell fails the $$G_1$$ checkpoint due to DNA damage. What is the most likely outcome?

Accepted Answer

The cell will attempt to repair the DNA or undergo apoptosis if repair is not possible

Question 12

Which process is responsible for the separation of the cytoplasm into two daughter cells?

Accepted Answer

Cytokinesis

Question 13

In a plant cell, what structure forms during cytokinesis to separate the two daughter cells?

Accepted Answer

Cell plate

Question 14

Which of the following best describes the difference between sister chromatids and homologous chromosomes?

Accepted Answer

Sister chromatids are identical copies formed during DNA replication; homologous chromosomes are similar but may have different alleles

Question 15

Which checkpoint ensures that all chromosomes are properly attached to the spindle before the cell proceeds with division?

Accepted Answer

M checkpoint

Question 16

A patient’s skin cells are observed to divide uncontrollably, forming a tumor. Which cell cycle process is most likely defective?

Accepted Answer

Cell cycle checkpoints

Question 17

Which of the following equations correctly represents the chromosome number in a human somatic cell before and after DNA replication?

Accepted Answer

$$2n = 46$$ before and $$2n = 46$$ after replication

Question 18

Which of the following is a direct result of the semiconservative nature of DNA replication?

Accepted Answer

Each daughter DNA molecule contains one parental and one new strand

Question 19

Which phase of the cell cycle is primarily responsible for cell growth and preparation for DNA synthesis?

Accepted Answer

$$G_1$$ phase

Question 20

A researcher observes a cell with decondensed chromosomes and two nuclei forming. Which stage is this cell most likely in?

Accepted Answer

Telophase

Cell Cycle, DNA Replication, and Mitosis: Study Notes for General Biology

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