Cell Fractionation Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

How do we study cells

A

Using light or electron microscopes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Characteristics of a light microscope

A

Lower magnification and resolution
Show images in colour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Characteristics of electron microscope

A

High magnification and resolution
Show images in black and white

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do we have to do to cells to see their cell components

A

Separate them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the stages to separating cell components

A

Homogenation
Filtration
Ultracentrifugation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What conditions should homegenates be placed in

A

Cold, buffered, isotonic solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why should homogenates be placed in a cold solution

A

Because it reduces enzyme activity (which could break down the organelles which is bad)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why should homogenates be placed in an isotonic solution

A

Prevents organelle suffering from plasmolysis or lysis as a result of osmotic gain or water loss, keeping the organelle from damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define isotonic solution

A

Solution has same H2O potential as the original tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why should homogenates be placed in a buffered solution

A

Maintains a constant pH so enzymes don’t denature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is enzyme activity bad for looking at cell components

A

Enzyme activity could break down organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens during homogenation

A

Disrupts the cell membrane, breaking open cells to release the organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why do we filter the homegenate

A

To remove large unwanted debris
Eg whole cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens during ultracentrifugation

A

The homogenate is centrifuged at a low speed
Remove the pellet of the heaviest organelle and respin the supernatent at a higher speed
Repeat at increasing speeds until til everything is separated out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Order of organelles heaviest to lightest

A

Heaviest - nuclei
Chloroplasts/mitochondria
Lysosomes
Endoplasmic reticulum
Lightest - ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly