chapter 3

Question 1

cell fractionation

Answer 1

to isolate different organelles

Question 2

why in cell fractionation organelles kept in iced cold solutions

Answer 2

to reduce enzyme activity and it could damage organelles

Question 3

why in cell fractionation organelles kept in buffered solution

Answer 3

pH buffer to prevent damage to organelles

Question 4

why in cell fractionation organelles kept in isotonic solution

Answer 4

water potential of solution and organelles are the same no osmosis prevents bursting or shrivel

Question 5

cell fractionation step 1

Answer 5

homogenization
cells are broken open with a blender
cells placed in a cold, isotonic, buffered solution
solution is filtered
removes debris

Question 6

prophase

Answer 6

chromatid condenses into chromosomes
nucleolus disappears
spindle fibers formed by centrioles

Question 7

metaphase

Answer 7

chromosomes line up along metaphase plate (equator)
spindle fibers released from the pole
attach to centromere

Question 8

anaphase

Answer 8

chromosomes break at centromere
sister chromatids move to opposite ends of the cells
ATP is required

Question 9

telophase

Answer 9

chromosomes at each pole of the cell
nuclear membrane reforms
nuclei reappear
chromosomes unwind into chromatin

Question 10

cytokinesis

Answer 10

when the cytoplasm splits and create two genetically identical cells

Question 11

ultracentrifugation

Answer 11

Once filtered, the homogenate solution is ready to be
centrifuged.
The solution is placed into a centrifuge
which spins at different speeds to separate organelles
depending on their density due to the centrifugal force