Mitosis

Question 1

Describe the structure of a chromosome

Answer 1

• each composed with 2 chromatids
• sister chromatids held together at the centromere
• telomeres protect DNA and don’t include genes

Question 2

what is mitosis

Answer 2

when the somatic cells of an organism divides into 2 identical cells

Question 3

what is the purpose of mitosis?

Answer 3

To produce 2 new nuclei with

• exactly the same kind and exactly the same number

of chromosomes in the parent cell

Question 4

why is mitosis important? (4)

Answer 4

• growth
• healing
• renewal
• asexual reproduction

Question 5

where does mitosis take place? (5)

Answer 5

• embryonic tissue
• epiphyseal plate of long bones
• bone marrow
• nasal layer of skin
• meristematic regions of plants

Question 6

Name the 5 phases of mitosis

Answer 6

IPMAT

Question 7

Describe Interphase in detail

Answer 7

• DNA has replicated
• can’t see the chromosomes very clearly
• animal cell has also made a copy of its centrosome
• still chromatin no chromosomes yet

Question 8

Discuss Prophase in full detail

Answer 8

• chromatin condenses to form chromosomes
• centrioles start to move to the poles
• spindle fiber begins to form between the centrioles
• the nuclear membrane and nucleus disappear

Question 9

Discuss Metaphase in full detail

Answer 9

• spindle fiber binds to the chromosomes at the kinetochore a patch of protein found on the centromere of each sister chromatid
• spindle pulls each chromosome to the middle of the cell -> metaphase line

Question 10

Discuss Anaphase in as much detail as possible

Answer 10

• centromere divides and splits

* sister chromatids separate from each other and are pulled towards opposite ends of the cell

Question 11

Almost done, Last one

Now, discuss Telophase

Answer 11

• cell is nearly done dividing & starts to re-establish its normal structures
• mitotic spindle is broken down and disappears
• 2 new nuclei form -> nuclear membranes and nucleoli reappear
• chromosomes begin to decondense & return to their “stringy” form as chromatin network

Question 12

what is cytokinesis?

Answer 12

• division of cytoplasm to form 2 new cells -> overlaps with final stages of mitosis
• may start in anaphase/telophase and finished shortly after telophase

Question 13

Difference between plant & animal cytokinesis

Answer 13

idk man ek is confused

Question 14

what is cancer?

Answer 14

uncontrolled mitosis

Question 15

what is the difference between a malignant and benign tumor?

Answer 15

malignant -> cell growth is not enclosed and cells can break away - cells can be carried vis the blood / lymph to other parts of the body

Benign -> growth of cells are enclosed in membrane or capsule - cells can’t escape to other parts of the body

Question 16

what can cause cancer? (4)

Answer 16

• Carcinogens

- environment 
- eat and drink 
- radiation / nuclear radiation