cell cycle, mitosis and meiosis

Question 1

interphase

Answer 1

G1- cell gets larger, copies organelles, molecular building blocks
S- the cells synthesizes a complete copy of the DNA in the nucleus. 2 sister chromatids. duplictaes centrosomes
G2- the cell grows more . makes protiens and organelles.

Question 2

prophase mitosis

Answer 2

Chromosomes start to condense
mitotic spindle beings to form, made of microtubules
nucleolus disappears.
mitotic spindles organise chromosomes
microtubules bind to chromosome at the centromere
chromosomes finish condensing
chromsomes lead by centromeres move to the equatorial plane - metaphase plate
nuclear envelope breaks down

Question 3

metaphase mitosis

Answer 3

chromosomes align at the metaphase plate
two kinetochores are attached to microtubles from opposite spindle poles. a spindle fibre form one pair of centrioles contracts one centromere and a spindle fibre attaches to the other centromere
spindle fibres shorten in length and contract
metaphase checkpoint- check if their kinetochores correctly attached to microtubules. spindle checkpoint. ensure that sister chromtids will split evenly between the two daughter cells

Question 4

anaphase mitosis

Answer 4

sister chromatids seperate from each other and pulled to oppiste ends of the cell (spindle fibres)
sister chromatids seperate
pulled to opposite ends of the cell
sister chromatids are now daughter chromosomes
driven by motor proteins

Question 5

telophase mitosis

Answer 5

miotic spindle broken down into building blocks
two new nuclei forms, nuclear membrane reform around the chromosomes around the other pole, of the cell and nucleoli reappear
Chromosomes begin to decondense

Question 6

cytokinesis mitosis

Answer 6

creates the seperation of cell in a pinch crease known as the cleavage furrow

Question 7

the new daughter cells mitosis

Answer 7

identical DNA

Question 8

prophase 1 mieosis

Answer 8

nuclear envelope disintegrates
chromosomes condense and pair up. homolgue partner.
trade parts (crossing over)
chiasmata keep the homologues connected to each other after the synaptonemal complex breaks down.
spindle fibres appear

Question 9

metaphase 1 meiosis

Answer 9

the spindle begins to capture chromosomes and move them towards the centre
each chromosome attaches to microtubule from one pole of the spindle and two homologues of a pair bind to microtubles from opposite poles. orientation is random

Question 10

anaphase 1 meiosis

Answer 10

spindle fibres contract and homologues are pulled apart and move to opposite ends of the cell

Question 11

telophase 1 and cytokinesis meiosis

Answer 11

chromosomes at opposite poles
decondense and nucear membrane may reform
2 non identical daughter cells, containing sister chromatids

Question 12

prophase ll

Answer 12

chromosomes condense and nuclear envelope breaks down
centrosomes move apart to opposite poles, spindles form between them and capture chromosomes.

Question 13

metaphase ll

Answer 13

line up along the metaphase plate
two sister chromatids of each chromosme are captured by microtubules from opposite spindle poles

Question 14

anaphase ll

Answer 14

the sister chromatids seperate and are pulled towards opposite poles of the cell.
spindle fibres contract to seperate the sister chromatids
move to opposite poles

Question 15

telophase ll and cytokinesis ll

Answer 15

nuclear membranes form around each set of chromosomes
chromosomes decondense
cytokinesis
splits the chromosome setas into new cells
four haploid cells chromosomes have just one chromatid

Question 16

mitosis vs meiosis

Answer 16

divison- mitosis involves only one cell division, but meiosis requires two cell divisions
independent assortment- homologous pairs are randomly seperated into seperate cells in meiosis, but not mitosis
synapsis- homologous pairs form bivalents in meiosis but not mitosis
crossing over- non-sister chromatids of homologous pairs may exchange genetic material in meiosis but not mitosis
genetics- cells produced by mitosis are genetically identical while cells produced by meiosis are genetically distinct