Mitosis

Question 1

Why does mitosis occur?

Answer 1

growth
repair / heal
asexual reproduction

Question 2

What are some examples of cells that are constantly dividing?

Answer 2

epithelial

intestinal

Question 3

What are some examples of cells that divide rarely / never?

Answer 3

brain - nerve
spinal cord - nerve
cardiac (heart muscle)

Question 4

What are the methods a cell can divide?

Answer 4

mitosis

meiosis

Question 5

What is the MAIN difference between mitosis and meiosis?

Answer 5

mitosis is division of somatic cells

meiosis is creation of new sex cells

Question 6

What are somatic cells?

Answer 6

all cells except for sex cells

genes will not be passed on

Question 7

What is a germ cell?

Answer 7

a cell destined to gamete

genes will be passed on

Question 8

What is diploid (2N)?

Answer 8

a cell pair with 2 chromosome sets in each of its cells

all body cells (SOMATIC CELLS)

Question 9

What is haploid (N)?

Answer 9

a cell with 1 chromosome set in each cell

all gamete cells

Question 10

Draw and annotate a somatic cell

Answer 10

CONGRATTTSSS YOOOU DDIIIDD IT !!!

Question 11

What are the features of a somatic cell?

Answer 11

plasma membrane
spindle microtubules
sister chromatids
centromere
centriole
telomere

Question 12

What are the characteristics of mitosis?

Answer 12

diploid cell will produce diploid cell

chromosome number remains the same

DNA remains identical of parent cell
one cell (2N) will produce 2 cells (both 2N)

nucleus of cell divides = 2 nuclei

Question 13

What is mitosis?

Answer 13

the part of cell division that results in 2 identical daughter cells from a single parent cell

Question 14

What are the stages of mitosis?

Answer 14

Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

Question 15

What happens in interphase?

Answer 15

does not involve cell division

DNA replicated

New organelles synthesised

cell increases in size (cytoplasm volume increases)

Question 16

What happens in prophase?

Answer 16

DNA supercoils - chromosomes appear

chromatin condenses and becomes sister chromatids (visible under light microscope)

centrioles seperate and spindles form

centrosomes move to opposite poles and spindle fibres form between them

LONGEST PHASE

Question 17

What happens in metaphase?

Answer 17

chromosomes line up at cell equator

spindle fibres attach to the centromere of each pair of sister chromatids

SHORTEST PHASE

Question 18

What happens in anaphase?

Answer 18

continued contraction of microtubule spindle fibres cause separation of sister chromatids

chromatids now referred to as chromosomes

chromosomes move to opposite poles

Question 19

What happens in telophase?

Answer 19

microtubule spindle fibres disappear

chromosomes uncoil to chromatin (no longer visible under light microscope)

new nuclear membranes reform around chromosomes

Question 20

What happens in cytokinesis (in general)?

Answer 20

cell fully separates into 2 identical daughter cells

Question 21

What happens in cytokinesis for animals?

Answer 21

a contractile ring (made of actin filaments) forms inside plasma membrane and pulls the cell equator inwards.
this creates a fissure called: CLEAVAGE FURROW

eventually splits into 2

Question 22

What happens in cytokinesis for plants?

Answer 22

in telophase golgi vesicles moved to centre of cell to form phragmoplast (vesicular structure). There they fuse to become cell plate, which will then become cell wall.

eventually splits into 2

Question 23

Why do plant and animal cells have different cytokinesis steps?

Answer 23

because the plant cell has a cell wall and the animal cell does not