Based on the model of eukaryotic cell cycle regulation shown in the figure, which of the following best describes the effect of a drug that blocks the production of the mitotic cyclin?

Question

BlackTom AI · Accepted Answer

In this question, we are considering how blocking the production of the mitotic cyclin would affect the eukaryotic cell cycle as depicted in the model.
Option 1 suggests that the G1 cyclin would substitute for the mitotic cyclin and allow normal division. While cyclins can have overlapping roles in some contexts, the mitotic cyclin specifically triggers entry into mitosis by activating CDKs necessary for chromosome condensation, spindle formation, and progression through mitosis. G1 cyclins primarily drive progression through G1 and the G1/S transition, not mitosis, so this substitution is not accurate.
Option 2 states that DNA synthesis would be prevented. DNA synthesis occurs during S phase and is regulated by cyclins associated with S phase and the G1/S transition, not directly by mitotic cyclin. Blocking mitotic cyclin would not halt DNA replication itself; cells could still enter S phase and replicate DNA if the earlier regulatory signals permit, so this answer misattributes the control point.
Option 3 posits that the cell cycle would proceed uncontrollably and become cancerous. A block in mitotic cyclin production would more likely impede progression into mitosis rather than cause uncontrolled division. Loss of mitotic cyclin activity would typically arrest cells before or during mitosis, not promote uncontrolled proliferation, making this option inconsistent with how cell cycle checkpoints function.
Option 4 asserts that the cell would be prevented from entering mitosis, and the cell would stop dividing. This aligns with the role of mitotic cyclin in activating CDKs that drive the cell into mitosis. Without mitotic cyclin, the G2/M transition cannot be properly executed, leading to an arrest before or at the point of mitotic entry and a cessation of cell division. This explanation fits the mechanistic understanding of cyclin-CDK regulation and the checkpoint controls that ensure orderly progression.
Therefore, the reasoning above supports that blocking mitotic cyclin production halts entry into mitosis and stops division, whereas the other options either misinterpret the regulatory roles of different cyclins or predict effects that are inconsistent with the designated block on mitotic progression.

APBIO141-031 with labs S12 - CollegeBoard* AP Exam Prep: Multiple Choice

Based on the model of eukaryotic cell cycle regulation shown in the figure, which of the following best describes the effect of a drug that blocks the production of the mitotic cyclin?

View Explanation

Log in for full answers

Similar Questions

Question at position 91 In eukaryotes the replication of chromosomal DNA occurs during:G2 phaseanaphaseG1 phaseprophaseS phase

If A, B, and C represent G1, S, and G2, respectively, then which phase of the cell cycle would you predict to last the longest in duration? Use the data shown in the left panel (Cells without treatment graph) to answer this question.

Use the figure to answer the question below. In the figure, why does the amount of DNA in nucleus decrease from IV to V?

After S phase of interphase, each chromosome contains two sister chromatids.

Chromosome replication in a somatic cell takes place during

During what portion of the cell cycle does interphase occur?

Question at position 36 DNA is replicated during the __________ subphase of interphase of the cell cycle.G1G2SM

More Practical Tools for Students Powered by AI Study Helper

Homework AI Solver

Stylized AI Paper Writer

Plagiarism Checker Assistant

Citation AI Academic Writing Tool

In-Class Translation Assistant

AI Note Generator

AI Quiz Answers

Past Exam Questions from University Test Bank

Smart Practice Assistant

Adaptive Practice

Making Your Study Simpler