Stages of mitosis

Question 1

What are the 3 stages of interphase

Answer 1

G1, S and G2

Question 2

What occurs during G1?

Answer 2

Cellular contents, excluding chromosomes is duplicated

Question 3

What checks occur at G1?

Answer 3

Size, nutrients, correct growth factors and DNA damage

Question 4

What is G0?

Answer 4

Cell cycle arrest

Question 5

What occurs at G0?

Answer 5

Stops cell division, differentiation and specialisation

Question 6

What occurs at S stage?

Answer 6

Each of the 46 chromosomes are duplicated by the cell

Question 7

What checks occur at S stage?

Answer 7

If the DNA replicated

Question 8

What occurs at G2?

Answer 8

The cell ‘double checks’ the duplicated chromosomes for error and making any needed repairs. Microtubules and relevant proteins are made also

Question 9

What checks occur at G2?

Answer 9

DNA errors and mistakes are repaired

Question 10

Where do checks occur during mitosis?

Answer 10

At the spindle assembly checkpoint

Question 11

What checks occur during mitosis?

Answer 11

Are the spindle fibres connected to the chromosomes to move them

Question 12

What are the types of microtubules involved in mitosis?

Answer 12

Aster, kinetochore and interpolar

Question 13

What are the 4 stages of mitosis?

Answer 13

Prophase, metaphase, anaphase and telophase

Question 14

What occurs during prophase?

Answer 14

1. Chromatin condenses and becomes visible.
2. The chromosomes consist of 2 identical sister chromatids, joined by a centromere.
3. Nuclear membrane breaks down.
4. Centrioles move to opposite poles of the cell and microtubules start to assemble around centrioles, forming the spindle.

Question 15

What occurs during metaphase?

Answer 15

1. Chromatid pairs attach to spindle microtubules at the centromere.
2. Chromatid pairs line up across the cell equator to form the metaphase plate

Question 16

What occurs during anaphase?

Answer 16

1. Centromeres divide
2. The sister chromatids are pulled apart by the spindle fibres to opposite ends of the cell

Question 17

What occurs during telophase?

Answer 17

1. The chromatids reach the poles of the spindle so they are now separate and are chromosomes
2. The chromosomes unravel and become indistinct.
3. The nuclear membrane reforms

Question 18

How does cell division occur in animal cells?

Answer 18

Many cells divide to allow organisms to grow and repair damaged structures

Question 19

How does cell division occur in plants?

Answer 19

Only specific areas undergo cell division - the meristem cells - so the shoot and root tails and just under bark so girth can increase

Question 20

What is cytokinesis?

Answer 20

The splitting of the cytoplasm

Question 21

What occurs during cytokinesis?

Answer 21

The nucleus has divided and 2 independant cells are formed with each being genetically identical to eachother and the parent cell