Cell Division

Question 1

Cell continuity

Answer 1

All cells develop from pre-existing cells

Question 2

Chromosomes

Answer 2

Coiled threads of DNA (40%) and protein (60%)

Question 3

Chromatin

Answer 3

Chromosomes when the cell is not dividing, these are long and thread like

Question 4

Genes

Answer 4

Units of inheritance

Question 5

Interphase

Answer 5

When a cell is not dividing

Question 6

Mitosis

Answer 6

When a cell divides

Question 7

How much of the cell cycle is interphase

Answer 7

90%

Question 8

What can DNA do during interphase

Answer 8

• transcription
• uncoiling
• chromosome doubling
• producing new organelles

Question 9

Mitosis definition

Answer 9

A form of nuclear division in which one nucleus divides to form two identical (daughter) nuclei. Each cell contains the same number of chromosomes with identical genes

Question 10

In what cells does mitosis occur?

Answer 10

Non reproductive cells (somatic)

Question 11

Stages of mitosis

Answer 11

Interphase
Prophase
Metaphase
Anaphase
Telophase

Question 12

Mitosis stages pneumonic

Answer 12

I (interphase)
Party (prophase)
Mondays (metaphase)
And (anaphase)
Tuesdays (telophase)

Question 13

Prophase

Answer 13

• Chromosomes become visible as double stranded structures
• Nuclear membrane breaks down
• Spindle fibres form in the cytoplasm

Question 14

Metaphase

Answer 14

• Nuclear membrane is now completely broken down
• A spindle fibre from each pole (end) of the cell attaches to the centromere
• The chromosomes line up along the equator of the cell

Question 15

Anaphase

Answer 15

• Spindle fibres contract, causing the centromeres to split
• One chromosome from each double stranded chromosome is pulled to opposite poles of the cell

Question 16

Telophase

Answer 16

• The chromosomes lengthen to form chromatin
• Spindle fibres break down
• Nuclear membrane forms around each chromatin

Question 17

Cell division in animals

Answer 17

Process called cleavage furrow

Question 18

Cell division in plants

Answer 18

• Cell wall prevents cytokinesis
• Vesicles form between the two nuclei, forming a cell plate
• New cell walls are created in the centre of the original plant cell, this space between them is called the middle lamella

Question 19

Function of mitosis for unicellular organisms

Answer 19

Reproduction e.g amoeba

Question 20

Function of mitosis in multicellular organisms

Answer 20

Growth and repair

Question 21

How many chromosomes are in each set in haploid cells

Answer 21

One set of chromosomes

Question 22

How many chromosomes are in each set in diploid cells

Answer 22

Two sets of chromosomes , i.e double-stranded chromosomes

Question 23

What symbolises haploid cells

Answer 23

‘n’

Question 24

What symbolises diploid cells?

Answer 24

‘2n’

Question 25

Example of haploid cells

Answer 25

Sperm and egg

Question 26

Diploid cell number for humans

Answer 26

2n = 46

Question 27

Meiosis

Answer 27

A form of nuclear division in which four daughter nuclei contain half the chromosome number of the parent nucleus

Question 28

Cancer

Answer 28

Cells which have lost the ability to control the rate of mitosis causing a group of disorders

Question 29

Types of tumours

Answer 29

Benign and malignant

Question 30

Benign tumours

Answer 30

Non- life threatening e.g warts and skin tags

Question 31

Malignant tumours

Answer 31

Life threatening

Question 32

Carcinogens examples

Answer 32

UV Radiation Cigarette Smoke

Question 33

Cancer treatments

Answer 33

Chemotherapy Radiation Therapy