Mitosis

Question 1

Definition of Mitosis

Answer 1

Its the form of cell division that occurs during the cell cycle

Question 2

What is mitosis needed for?

Answer 2

> The growth of multicellular organisms
For repairing damaged tissues
Some animals, plants and fungi also use it to reproduce asexually

Question 3

Describe the structure of Chromosomes

Answer 3

> They are made up of two Chromatids joined in the middles by a centromere
Two strands on the same chromosome are called sister chromatids

Question 4

What are the 6 phase of Mitosis

Answer 4

1. Interphase
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase
6. Cytokinesis

Question 5

What happens during Prophase

Answer 5

> The chromosomes condense getting shorter and fatter.
Centrioles start move to opposite ends of the cell, forming a network of protein fibres across it called the spindle.
The nuclear envelope breaks down and chromosomes lie free in the cytoplasm

Question 6

What happens during Metaphase

Answer 6

> The chromosomes line up along the middle of the cell (at the spindle equator) and become attached to the spindle by their centromere

Question 7

What happens at the metaphase checkpoint?

Answer 7

The cell checks that all the chromosomes are attached to the spindle before mitosis can continue

Question 8

What happens during Anaphase

Answer 8

> The centromeres divide, separating each pair of sister chromatids.
The spindles contract, pulling chromatids ti opposite ends of the cell, centromere first

Question 9

What happens during Telophase

Answer 9

> The chromatids reach the opposite poles on the spindle.
They uncoil and become long and thin again - now called chromosomes again.
A nuclear envelope forms around each group of chromosomes - so there are now two nuclei

Question 10

definition of cytokinesis

Answer 10

The division of the cytoplasm of a cell following mitosis

Question 11

when does cytokinesis begins and ends?

Answer 11

Begins in anaphase and ends in telophase