cell division

Question 1

what happens in prophase I

Answer 1

chromosomes condense
centrioles move to the pole
nuclear membrane breaks down
centrioles start to make spindle fibres

Question 2

what happens during the bivalent formation

Answer 2

chromosomes cross over
certain genes are transferred

Question 3

what is synapsis

Answer 3

the process of pairing up homogolous chromosomes

Question 4

what is a chiasma

Answer 4

the point at which chromosomes cross over

Question 5

what happens during metaphase I

Answer 5

4 chromatids line up at equator
centromere attaches the chromosome to the spindle

Question 6

what happens during anaphase I

Answer 6

bivalent seperation (pull chromosomes apart)
centromeres do not divide (break apart chaisma)

Question 7

what happens during telophase I

Answer 7

2 new nuclear envelopes form

Question 8

what is a gene locus

Answer 8

position of a gene on a chromosome

Question 9

what happens during the process of synapsis

Answer 9

the process of pairing up the homologous chromosomes

Question 10

what is the asexual reproduction in yeast

Answer 10

budding

Question 11

outline the process of the asexual process in yeast

Answer 11

mitosis

small bud emerges from mother cell
enlarges until it reaches a certain size
separates from the mother cell

Question 12

why does genetic material need to replicate before the nucleus is divided (2 marks)

Answer 12

genetically identical
correct amount of DNA

Question 13

what is a homologous pair of chromosomes (3 marks)

Answer 13

maternal and paternal genes
carry same genes
carry same alleles

Question 14

what is the function of squamous epithelium

Answer 14

acts as a surface

Question 15

where is squamous epithelium found

Answer 15

alveoli

Question 16

give 2 examples of where to find meristem tissue

Answer 16

root
shoot

Question 17

what is the nuclear division that occurs in meristem

Answer 17

mitosis

Question 18

what are the stages of the cell cycle

Answer 18

interphase
mitotic
cytokinesis

Question 19

what are the 3 stages in interphase

Answer 19

G1
S
G2

Question 20

what happens in G1 (2 ways)

Answer 20

cell size doubles
cell synthesis

Question 21

what happens in the S phase of interphase

Answer 21

DNA replicates

Question 22

what happens in G1

Answer 22

organelles divide

Question 23

give 3 reasons why mitosis occurs

Answer 23

growth
cell repair
asexual reproduction

Question 24

what are the 4 phases of the mitotic phase

Answer 24

prophase
metaphase
anaphase
telophase

Question 25

what are the 3 things that occur in prophase

Answer 25

chromosomes condense
centrioles move to opposite sides of the cell
nuclear envelope and nucleolus breaks down

Question 26

what happens in metaphase

Answer 26

chromatids line up on the equator

Question 27

what happens in anophase

Answer 27

spindle fibres contract
chromatids seperate into 2 different chromosomes and are pulled to opposite poles of the cell
spindle fibres break down

Question 28

what happens in telophase

Answer 28

chromsomes decondense
nuclear envelope form around each set of chromosome

Question 29

what are the 2 things that happen in cytokinesis

Answer 29

cell membrane forms cleavage furrow
division of cytoplasm

Question 30

what enzyme and protein initates the next phase of the cell cycle after a checkpoint

Answer 30

kinase enzymes
phosphorylate proteins

Question 31

what are the products of meiosis

Answer 31

4 haploid cells
half the number of DNA

Question 32

what are the