Q6: Stages Of Mitosis

Question 1

Mitosis

Answer 1

Produces two daughter cells in that have the same number of chromosomes as the parent cell and each other and an exact copy of DNA.

Question 2

Two daughter nuclei and parent nucleus …

Answer 2

Have identical genetic make up.

Question 3

Exception to genetic make up of daughter cells and parent cell nuclei having the same genetic make up?

Answer 3

Mutation

Question 4

Interphase

Answer 4

Period preceding mitosis when the cell is not dividing and considerable cellular activity occurs including the replication of DNA.

Question 5

What happens to the two copies of DNA after DNA replication during interphase?

Answer 5

Remain joined at the centromere.

Question 6

Mitosis

Type of process

Answer 6

Continuous process

Question 7

Mitosis can be divided into four stages

Answer 7

Prophase
Metaphase
Anaphase
Telophase

Question 8

Centrioles

Answer 8

2 Cylindrical organelles in each animal cell

Move to poles of cell and spindle fibres develop from them

Question 9

Collective term for spindle fibres

Answer 9

Spindle apparatus

Question 10

Prophase

6 steps

Answer 10

1. Chromosomes become visible as long, thin threads.
2. Chromosomes shorten and thicken.
3. Centrioles move to the poles of the cell.
4. Spindle fibres develop from each of the centrioles, span from pole to pole
5. Nucleolus disappears and nuclear envelop breaks down
6. Chromosomes left free in the cytoplasm and are draw towards the equator of the cell by spindle fibres.

Question 11

Metaphase

2 steps

Answer 11

1. Chromosomes are seen to be made up of two chromatids which are joined by the centromere
2. Spindle apparatus pulls chromatids to arrange themselves along the equator of the cell

Question 12

Anaphase

3 steps

Answer 12

1. Centimetres divide into two and the spindle fibres pull the individual chromatids apart
2. Chromatids move to their opposite poles - referred to as chromosomes again
3. Mitochondria provide the energy for this process and gather round spindle fibres

Question 13

What happens to the chromosomes in cells which are treated with chemicals

Answer 13

Spindle fibres are destroyed

Chromosomes remain at the equator

Question 14

Telophase

Answer 14

1. Chromosomes reach poles and become longer and thinner, then disappear, leaving widely spread chromatin
2. Spindle fibre disintegrate
3. Nuclear envelope and nucleolus reform

Question 15

Cytokinesis

Answer 15

Cytoplasm divides

Question 16

When does cytokinesis happen

Answer 16

After telophase