cell fractionation

Question 1

in differential centrifugation why do we chop up the tissue in an ice cold isotonic buffer

Answer 1

chopping-increases surface area
ice cold-prevents enzyme damaging organelles
isotonic- prevents osmosis and bursting of organelles
buffer-balances pH

Question 2

what is cell fractionation

Answer 2

the process where cells are broken up and the diffefrent organelles are then separated out

Question 3

what is differential centrifugation

Answer 3

the process of separating organelles

Question 4

in differential centrifugation why do we homogenise

Answer 4

breaks the cell membrane and wall so organelles are freed

Question 5

in differential centrifugation why do we filter the homogenate

Answer 5

removes large pieces/debris

Question 6

in differential centrifugation why do we spin it in a centrifuge

Answer 6

denser parts of the homogenate are spun to the bottom of the tube

Question 7

in differential centrifugation why do we pour of the supernatent

Answer 7

pellet contains nuclei the we respin supernatent to get other organelles

Question 8

what are the steps of differential centrifugation

Answer 8

chop up tissue in an ice cold isotonic biffer solution
homogenise
filter homogenate
spin in centrifuge
keep sesiment and pour off supernatent