Question

A cell undergoes a nuclear division and separation of cytoplasm, after which the number of cellular organelles is doubled, and cell size increases greatly. However, a malfunctioning enzyme (DNA helicase) prevents the separation of the DNA strands.

What is the consequence of this malfunction?
Responses

Anaphase during the S phase cannot occur.
Anaphase during the S phase cannot occur.

DNA replication during the G1 phase cannot occur.
DNA replication during the G1 phase cannot occur.

Anaphase during the G1 phase cannot occur.
Anaphase during the G1 phase cannot occur.

DNA replication during the S phase cannot occur.

Answer 1

The consequence of the malfunctioning DNA helicase enzyme, which prevents the separation of the DNA strands, would affect the DNA replication process. Specifically, helicase is responsible for unwinding the DNA double helix in preparation for replication. If it is malfunctioning, the DNA strands cannot be separated and therefore DNA replication cannot take place.

Given this information, the correct response would be:

**DNA replication during the S phase cannot occur.**

This aligns with the idea that the S phase (Synthesis phase) of the cell cycle is where DNA replication occurs, and if helicase cannot separate the strands, replication will be impeded.