Cell cycle

Question 1

What must happen before cytokinesis (cell splitting)

Answer 1

Karyokinesis (nucleus splitting)

Question 2

What are the stages of the cell cycle

Answer 2

Interphase
Mitosis
Cytokinesis

Question 3

What are the phases of mitosis

Answer 3

Prophase
Metaphase
Anaphase
Telophase

Question 4

What are phases of meiosis

Answer 4

Early prophase 1
Late prophase 1
Metaphase 1
Anaphase 1
Telophase 1
Prophase 2
Metaphase 2
Anaphase 2
Telophase 2

Question 5

When do mutations occur in the cell cycle

Answer 5

S phase of interphase

Question 6

What is a proto-onco gene

Answer 6

Genes that start the cell cycle

Question 7

What is a tumour-suppressor gene

Answer 7

Slows the cell cycle

Question 8

What are chiasmata

Answer 8

Points of contact between chromatids which, in meiosis, causes variation through crossing over as genes are transferred from one chromatid to another

Question 9

In what phase of meiosis do chiasmata occur

Answer 9

Late prophase 1

Question 10

What is independent assortment

Answer 10

In meiosis, during metaphase 1, the chromosomes line up randomly, allowing for a random separation of chromosomes, causing variation

Question 11

What happens in prophase in mitosis

Answer 11

The chromosomes condense making them visible

Question 12

What happens in metaphase in mitosis

Answer 12

The chromosomes line up on the equator of the spindle

Question 13

What happens in anaphase in mitosis

Answer 13

The centromere splits so the chromatids separate and are pulled to either end of the cell along the spindle

Question 14

What happens in telophase in mitosis

Answer 14

Nuclear membranes appear around each group of chromatids at either end of the cell. The spindle fibres fade away

Question 15

What happens in early prophase 1 in meiosis

Answer 15

The chromosomes condense making them visible

Question 16

What happens in late prophase 1 in meiosis

Answer 16

Homologous chromosomes come together, forming two bivalents. Crossover points occur and genes can be transferred to different chromatids

Question 17

What happens in metaphase 1 in meiosis

Answer 17

The bivalents line up on the equator of the spindle

Question 18

What happens in anaphase 1 in meiosis

Answer 18

Bivalents separate and homologous chromosomes are pulled to either end of the cells. The centromere does not break.

Question 19

What happens in telophase 1 in meiosis

Answer 19

The chromosomes arrive at either end of the cell and a nuclear membrane forms around each group and the cell splits.

Question 20

What happens in prophase 2 of meiosis

Answer 20

The centrioles form new spindles at right angles to the original spindles

Question 21

What happens in metaphase 2 of meiosis

Answer 21

The chromosomes line up on the equators of the spindles

Question 22

What happens in anaphase 2 of meiosis

Answer 22

The centromeres split so the chromatids separate and travel to either end of the cells along the spindle fibres

Question 23

What happens in telophase 2 of meiosis

Answer 23

Nuclear membranes form around all four groups of chromatids and the cells divide, producing four genetically unique daughter cells