-produce energy in the form of the carrier molecule ATP. -release energy in aerobic respiration.
17 of 30
what is osmotic lysis?
the splitting/breaking of cells because of too much water.
18 of 30
what is the function of the cell wall in a prokaryotic cell?
prevent osmotic lysis.
19 of 30
what are the optional structures in a prokaryotic cell?
slime capsule, mesosome, plasmids, flagellum
20 of 30
what is cell fractionation?
the process of breaking open cells to release different organelles by separating them.
21 of 30
what does the tissue have to be placed in before the process can begin and why?
ice cold water- to reduce enzyme activity which may break down organelles. -isotonic to prevent osmotic lysis because it has the same water potential as the tissue. -buffered to maintain a constant pH so enzymes aren't denatured.
22 of 30
describe the first stage.
homogenisation- cells broken up by blender to release organelles to make a homogenate. It is then filtered to remove complete cells and debris.
23 of 30
describe the second stage.
ultracentrifugation- organelles are separated in a centrifuge and the most dense/largest are spun down first.
24 of 30
describe the sequence in which things are spun down.
nuclei then mitochondria then ribosomes.
25 of 30
what is the maximum magnification of a light microscope?
x1500
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what is their resolving power like?
low because they have long wavelengths.
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what is the resolving power of electron microscopes like?
high because of short wavelengths.
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what are the disadvantages of electron microscopes?
-images in black and white. -everything seen must be dead.
29 of 30
what is the difference between the TEM and the SEM?
TEM- high resolution and 2D image. SEM- low resolution and magnification and 3D image.
30 of 30
Other cards in this set
Card 2
Front
give an example of a prokaryotic cell.
Back
bacteria
Card 3
Front
give examples of eukaryotic cells.
Back
Card 4
Front
outline the differences of prokaryotic and eukaryotic cells
Back
Card 5
Front
is an epithelial cell eurkaryotic or prokaryotic, and where is it found?
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