Mitosis POGIL

List the four phases in the mitosis process.

Telophase, Metaphase, Prophase, and Anaphase

Where is mitosis in the cell cycle (Before and after)

(Before): G1/cytokinesis (After): G2/S(ynthesis)

What three phases of the cell cycle are considered interphase?

G1, G2, S

How many cells are present at the beginning of mitosis?

one

How many cells are present at the end of mitosis?

two

How many chromatids are in each replicated chromosome?

two sister chromatids

How many replicated chromosomes are in the original cell during prophase?

four

How many single chromosomes are in each of the new cells in telophase?

four each

What is a chromosome and why is it important?

A chromosome is made of DNA wrapped around proteins and contains all the genetic information for an organism.

What might the new cells in telophase contain if replication of chromosomes did not occur before cytokinesis? Would cells be viable?

The new cells might only contain only half the original number of chromosomes, or one cell might contain more chromosomes than the other if replication did not occur before cytokinesis. They would not be viable. They wouldn't have a complete set of DNA.

Why do you think the cell needs to make more DNA during the S(ynthesis) phase in the cell cycle?

The cell must copy the chromosome material so if there is enough to make two new cells with the correct chromosome number.

During what phase of the cell cycle do you think the chromosomes are replicated?

Synthesis

In which phase of mitosis do you see the spindle fibers forming?

Prophase

At what phase of mitosis do the replicated chromosomes (sister chromatids) separate?

Anaphase

In which phase do you see that the spindle fibers have disappeared?

Telophase

Suggest the purpose of the spindle fibers during mitosis.

The spindle fibers separate the replicated chromosomes and move each single chromosome to the opposite sides of the cells.

Describe what happens to the nuclear membrane after prophase.

It breaks down.

Explain why it is necessary that the nuclear membrane disintegrates during mitosis.

It must be temporarily removed for the chromosomes to be divided into two cells.

At what point during mitosis has the nuclear membrane reformed?

Telophase

What is actually dividing during cytokinesis?

Cytoplasm

Cellular division has two parts-mitosis is the division of the nucleus and cytokinesis is the division of the cell into two new cells. Explain why mitosis has to come before cytokinesis in the cell cycle.

The contents of the nucleus must be duplicated and the chromosomes must be correctly divided up before the actual cell can divide into two new cells.

Why does the DNA must coil up into chromosome structures before it divides?

If they're long and thin, pieces of DNA can be lost. Certain pieces can be broken off.

Prophase

Chromosomes become visible, each replicated chromosome is made of two identical chromatids, spindle fibers begin to form and nuclear membrane begins to disintegrate.

Metaphase

Chromosomes line up in middle of the cell, spindle fibers attach to replicated chromosome at their centers.

Anaphase

Spindle fibers separate sister chromatids into separate chromosomes and move them to opposite sides of the cell.

Telophase

Single chromosomes are in two "piles" that will become two nuclei. New nuclear membrane begins to form around the two piles of separated chromosomes.

Cytokinesis

Original cell pinches in two and makes two new cells.

In some cells, mitosis occurs without cytokinesis. What would the resulting cell look like?

The cell would be multinucleated.

Why is mitosis important in a skinned knee and during the growth of the plant?

New cells must form for a skinned knees/to regrow blood vessels and skin. Also to grow plants to make it bigger.

What would the effect be on a cell if the sister chromatids did not line up correctly during metaphase. For example, if some lined up side by side instead of single file along the middle, how might this affect the resulting cells?

If the division of cells are not accurate, cells could end up with too few or too many chromosomes. This could lead to the death of a cell or mutation.

Describe the effects on mitosis in a cell that has been treated with colchicine.

The spindle fibers would not be formed correctly. Chromosomes would not be able to divide correctly.

Predict how binary fission in prokaryotic cells might be different from mitosis in eukaryotic organisms.

Less complicated than mitosis. Single chromosome is copied and cell is pinches into two new cells, each with a single chromosome.