Question 1

Which of the following best describes the primary purpose of mitosis in multicellular eukaryotes?

Accepted Answer

To generate two genetically identical daughter cells for growth, repair, and development

Question 2

During which phase of the cell cycle does DNA replication occur, and what is the result of this process?

Accepted Answer

S phase; each chromosome is duplicated to form two sister chromatids

Question 3

A scientist observes a cell with chromosomes aligned at the center of the cell, attached to spindle fibers. Which stage of mitosis is this, and what is the significance of this arrangement?

Accepted Answer

Metaphase; chromosomes are aligned at the metaphase plate to ensure equal segregation

Question 4

Which of the following statements about the mitotic spindle is correct?

Accepted Answer

It is assembled from microtubules that originate from centrosomes

Question 5

A mutation causes a cell to ignore the G1 checkpoint. Which of the following is a likely consequence?

Accepted Answer

The cell may divide uncontrollably, potentially leading to cancer

Question 6

Platelet-derived growth factor (PDGF) is important in wound healing because it:

Accepted Answer

Stimulates fibroblasts to divide and repair damaged tissue

Question 7

Which of the following equations correctly represents the chromosome number in human somatic cells and gametes?

Accepted Answer

$$2n = 46 in $$somatic cells; $$n = 23 in $$gametes

Question 8

A researcher adds a chemical that prevents the formation of the contractile ring in animal cells. What process will be directly inhibited?

Accepted Answer

Cytokinesis

Question 9

Which of the following best explains why cancer cells can form tumors, while normal cells do not under the same conditions?

Accepted Answer

Cancer cells ignore signals such as density-dependent inhibition and anchorage dependence

Question 10

If a cell has 8 chromosomes at the beginning of G1, how many chromatids will it have after S phase is complete?

Accepted Answer

16

Question 11

Which of the following is a function of cyclin-dependent kinases (Cdks) in the cell cycle?

Accepted Answer

They phosphorylate target proteins to regulate cell cycle progression

Question 12

A cell is observed to have a single layer of cells that stop dividing once they fill a gap. This behavior is best described as:

Accepted Answer

Density-dependent inhibition

Question 13

Which checkpoint is considered the most important in many cells, and what happens if a cell does not receive the go-ahead signal at this checkpoint?

Accepted Answer

G1 checkpoint; the cell enters a non-dividing G0 state

Question 14

Which of the following best describes the difference between mitosis and meiosis?

Accepted Answer

Mitosis produces two genetically identical cells, while meiosis produces four genetically unique gametes

Question 15

A plant cell is observed forming a cell plate during division. What is the significance of this structure?

Accepted Answer

It develops into a new cell wall, separating the two daughter cells

Question 16

Which of the following best explains why DNA must be precisely replicated before cell division?

Accepted Answer

To ensure each daughter cell receives a complete and identical set of genetic information

Question 17

If a cell is exposed to a drug that prevents the breakdown of cohesins, what would most likely occur during mitosis?

Accepted Answer

Sister chromatids would fail to separate during anaphase

Question 18

Which of the following is true regarding the role of the centromere during mitosis?

Accepted Answer

It is the site where spindle fibers attach to chromosomes via kinetochores

Question 19

A cell is observed to have two centrosomes at opposite poles and chromosomes attached to spindle fibers but not yet separated. Which stage is this, and what is the next major event?

Accepted Answer

Metaphase; sister chromatids will separate and move to opposite poles

Question 20

Which of the following best describes the relationship between cyclins and cyclin-dependent kinases (Cdks) in cell cycle regulation?

Accepted Answer

Cyclins bind to Cdks, activating them to regulate cell cycle transitions

The Cell Cycle: Chapter 12 Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard