Question

1. refer to the cells in telophase in model 1.

a. use a complete sentence to describe what the new cells in telophase might contain if replication of chromosomes did not occur before cytokinesis.
b. if the situation in part a occurred, would the new cells be viable? explain.

1. the s phase stands for synthesis, which means to make or build something more complex out of simpler parts. scientists know that during the s phase dna is being made in the nucleus of the cell. why do you think the cell needs to make more dna at this time in the cell cycle?
2. refer to model 1. the chromosomes that are shaped like \x\ (made of two sister chromatids) have double the amount of dna than the chromosomes that are shaped like \i.\ during what phase of the cell cycle do you think the chromosomes are replicated (copied)?

Explanation:

For Question 9a:

Telophase is the final stage of mitosis where cells split; without prior chromosome replication, each new cell would only receive half the normal number of chromosomes (one copy instead of two) from the parent cell.

For Question 9b:

Viable cells need a full set of genetic material to produce necessary proteins and carry out all cellular functions. Cells with only half the chromosomes lack critical genetic information, so they cannot function properly or survive long-term.

For Question 10:

The S phase occurs before cell division (mitosis). Making more DNA ensures that when the cell divides, each new daughter cell receives an identical, full set of genetic material to match the parent cell.

For Question 11:

The S (synthesis) phase is defined as the stage where DNA replication takes place, which creates the sister chromatids that form the "X-shaped" chromosomes seen later in the cell cycle.

Answer:

9a. If chromosome replication did not occur before cytokinesis, the new cells in telophase would each contain only half the normal number of chromosomes that a functional body cell should have.
9b. No, the new cells would not be viable. They would lack the full set of genetic information required to produce all the proteins and carry out all the essential functions needed for the cell to survive and operate properly.

1. The cell needs to make more DNA during the S phase to ensure that each of the two new daughter cells produced during cell division receives an identical, complete set of genetic material, matching the genetic content of the original parent cell.
2. The chromosomes are replicated (copied) during the S (synthesis) phase of the cell cycle.