Interphase
Prophase
Metaphase
Anaphase
Telophase/Cytokinesis
100
When does interphase take place?
Before mitosis begins; at the beginning of the cell cycle.
100
True or False: centrioles move to the opposite ends of the cell.
False; centrioles move to the opposite ends of the nucleus.
100
Where do chromosomes line up in metaphase?
In the middle of the cell.
100
What is the main function of anaphase?
The chromosomes are pulled away and separated by the spindle fibers to the opposite ends of the cell.
100
True or false: chromosomes stay condensed in telophase.
False; they de-condense.
200
What happens in the S phase of interphase and why is it necessary?
DNA makes an extra copy of itself, which is needed for the new daughter cell that will form at the end of mitosis.
200
What happens to DNA in prophase?
They condense into chromosomes.
200
What do spindle fibers do in metaphase?
They attach to the centromeres on the chromosome.
200
Why do chromosomes have to be pulled to the opposite ends of the cell?
This ensures the when the cell splits in half, only one group of chromosomes are in the new daughter cell.
200
What forms at the end of telophase?
Two new nuclei form at opposite ends of the cell.
300
Name two organelles that are replicated in the _____ phase.
Ribosomes, mitochondria as well as chloroplasts are among the organelles replicated in the G1 (growth) phase of interphase.
300
When does mitosis begin in prophase?
After the chromosomes condense and the nuclear membrane breaks down.
300
What is the mechanism behind the chromosomes' alignment?
After the spindle fibers attach to the centromeres, they pull the chromosomes into line in the middle of the cell.
300
What happens to the spindle fibers once they finish pulling the chromosomes away?
They detatch from the centromeres and dissolve.
300
What remains to be done at the end of telophase?
Cytokinesis, the cell must be split into two.
400
A cell with defected DNA is allowed to proceed into mitosis? What phase in interphase went wrong?
The G2 phase.
400
Describe what will happen in metaphase if chromosomes fail to condense.
Because the DNA has not condensed, it will stay in its "spaghetti" form and not be able to align in the middle of the cell.
400
If the spindle fibers don't form in prophase, what will happen to the chromosomes during metaphase and the later phases of mitosis?
The chromosomes won't be able to align in the middle of the cell and mitosis will not be able to continue into anaphase.
400
Why is it important that chromosomes separate?
Mitosis fails; if the chromosomes failed to separate, then the genetic information in the chromosomes would fail to be passed onto the new daughter cell.
400
There is a defect in the cell membrane that makes the membrane rigid and inflexible. How does this affect cytokinesis?
It would be highly unlikely that the cell would be able to split into two new cells.
500
A scientist has made two types of cells with different interphases: one cell type does not undergo the G1 phase and the other cell type does not undergo the S phase. Which cell type will be able to proceed into mitosis and how is it different than a normal cell undergoing mitosis?
The cell that does not undergo the G1 phase can still divide because its DNA has been replicated for the second daughter cell at the end of mitosis. However, because the cell does not grow and duplicate organelles, the daughter cells produced at the end of mitosis will get smaller and smaller.
500
Imagine the nuclear membrane fails to dissolve. What would this mean for the rest of the mitosis stages and what would happen to the cell?
If the rest of mitosis proceeds, the chromosomes will be unable to move to opposite ends of the cell, the two nuclei in telophase will be unable to form and the cell will be unable to divide in half in cytokinesis.
500
Why must the chromosomes align in the middle of the cell?
This is a way of the cell checking that all chromosomes are in order and ready to be separated. If they're not then mitosis will not proceed.
500
Before the separation of the chromosomes, a toxin dissolves the spindle fibers yet mitosis still proceeds. What are the consequences to the cell and the chromosomes?
Only one of the two daughter cells will inherit the chromosomes and will have double the genetic information needed, which can cause problems in cellular function.
500
The cell pinches in half closer to the right end of the cell than the middle. Name two potential effects on the daughter cells.
One cell has more organelles than the other cell. One cell might have more mitochondria than the other cell and therefore produce more energy. Performing normal cellular functions might be more difficult for one cell than the other.
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