cell division

Question 1

when does the cell cycle start

Answer 1

when a cell has been produced by cell division

Question 2

what happens in G1

Answer 2

the cell grows and doubles its organelles

Question 3

what happens at the g1 checkpoint

Answer 3

cell checks that the chemicals needed for replication are present and for any damage to DNA

Question 4

what happens at the s phase

Answer 4

cell replicates DNA and is ready to divide by mitosis

Question 5

what happens at G2 checkpoint

Answer 5

replicated DNA is checked for any mutations and if there isnt any it will start mitosis

Question 6

what happens in the M phase

Answer 6

mitosis and cytokinesis

Question 7

what 2 reasons do cells need to divide

Answer 7

repairing damaged tissues
asexual reproduction

Question 8

why does interphase happen before mitosis

Answer 8

to allow cells to replicate their DNA ready for division

Question 9

what happens during interphase

Answer 9

cells dna is replicated, organelles replicated

Question 10

in prophase what condenses

Answer 10

chromosomes - making them shorter and fatter

Question 11

what starts to move to opposite ends

Answer 11

centrioles

Question 12

what do centrioles form

Answer 12

spindle fibres

Question 13

what happens to the nuclear envelope during mitosis

Answer 13

it breaks down

Question 14

what happens at metaphase

Answer 14

chromosomes line up along the middle of the cell

Question 15

what do the chromosomes become attached to at metaphase

Answer 15

spindles

Question 16

what happens at M1 checkpoint

Answer 16

cell checks chromosomes are attached to the spindle

Question 17

what happens during anaphase

Answer 17

centrioles divide

Question 18

what gets separated during anaphase

Answer 18

sister chromatids

Question 19

what happens to the spindle during the anaphase

Answer 19

they contract pulling the cell apart

Question 20

what happens during telophase

Answer 20

chromatids reach opposite poles and become chromosomes again

Question 21

what happens to the nucleus in telophase

Answer 21

it divides into 2 nuclei

Question 22

what happens in cytokinesis

Answer 22

cytoplasm divides forming two genetically identical cells

Question 23

what forms in animal cells to divide the cell membrane

Answer 23

cleavage furrow

Question 24

why is meiosis important

Answer 24

for the production of gametes

Question 25

what happens during prophase 1 of meiosis

Answer 25

chromosomes condense and arrange themselves into homologous pairs

Question 26

what is a homologous pair

Answer 26

when chromosomes pair up during reproduction

Question 27

what happens to the nuclear envelope in prophase 1

Answer 27

it breaks down

Question 28

what happens during the anaphase 1 of meiosis

Answer 28

spindles contract which separates homologous pairs

Question 29

what happens during telophase 1

Answer 29

nuclear envelope forms around each group of chromosomes

Question 30

what happens during the second stages of meiosis

Answer 30

all of the same stages twice

Question 31

what are sister chromatids

Answer 31

the individual strands that ,make up a chromosome

Question 32

what happens during anaphase II

Answer 32

sister chromatids are separated

Question 33

what is the product of meiosis

Answer 33

4 genetically different haploid daughter cells called gametes

Question 34

meiosis forms a -------- cell

Answer 34

haploid

Question 35

mitosis forms a ----- cell

Answer 35

diploid

Question 36

what is a stem cell

Answer 36

an undifferentiated cell that can differentiate into different cells

Question 37

what are stem cells used for in adults

Answer 37

to replace damaged cells

Question 38

what are stem cells used for in plants

Answer 38

various plant tissues including xylem and phloem

Question 39

main bones in the body contain what

Answer 39

bone marrow

Question 40

what do adult stem cells do in bone marrow

Answer 40

divide and differentiate

Question 41

what is a erythrocyte

Answer 41

a red blood cell

Question 42

what is a neutrophil

Answer 42

a white blood cell

Question 43

where are stem cells found in plants

Answer 43

meristems

Question 44

what 2 brain diseases do researches hope to cure with stem cells

Answer 44

Alzheimer's and Parkinson's

Question 45

what do researches hope to do with stem cells in Alzheimer's disease

Answer 45

regrow healthy nerve cells

Question 46

what do researches hope to do with stem cells in Parkinson's disease

Answer 46

regenerate dopamine producing cells

Question 47

where do neutrophils and erythrocytes come from

Answer 47

bone marrow

Question 48

how are neutrophils specialised

Answer 48

flexible shape which helps them engulf pathogens lots of lysosomes which help them break down engulfed particles

Question 49

how are erythrocytes specialised

Answer 49

large surface area no nucleus so more room for haemoglobin

Question 50

how are epithelial cells specialised

Answer 50

joined by interlinking membranes

Question 51

how are ciliated epithelia specialised

Answer 51

contain cilia which help them move

Question 52

how are squamous epithelia specialised

Answer 52

very thin for efficient diffuison

Question 53

how are sperm cells specialised

Answer 53

flagellum( tail) which helps them swim to the egg lots of mitochondria digestive enzymes in head for penetration of egg

Question 54

what is the function of the palisade mesophyll

Answer 54

does most of photosynthesis

Question 55

how is the palisade mesophyll specialised

Answer 55

contain many chloroplasts thin walls so carbon dioxide can easily diffuse into the cell

Question 56

how are root hair cells adapted

Answer 56

large surface area and a thin cell wall extra mitochondria for energy during active transport

Question 57

What process occurs in metaphase one

Answer 57

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