Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AQA Biology > 2.2 Cell Studies > Flashcards

2.2 Cell Studies Flashcards

1
Q

What is the advantage of electron microscopes?

A

Higher resolution

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

Why do electron microscopes have a higher resolution?

A

Electrons have a shorter wavelength

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

How do optical microscopes work?

A

Focus a beam of light through specimen

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

How do electron microscopes work?

A

Focus a beam of electrons through specimen

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

What is the advantage of optical microscopes?

A

Specimen can be alive

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

What are the types of electron microscope?

A

Transmission Electron Microscope
Scanning Electron Microscope

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

Describe the preparation of a slide for a TEM.

A

Thin so electrons can penetrate

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

Which microscope can see specimens in colour?

A

Optical/light

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

What is the disadvantage of TEM slide preparation?

A

Complex staining technique

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

Which microscope allows smaller orgamelles to be seen?

A

TEM

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

Why do samples for a light microscope need to be thin?

A

Light can pass through
Only one layer of cells can be seen

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

What is an eyepiece graticule?

A

Apparatus that goes over eyepiece with a ruler

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

Why do eyepiece graticules need to be calibrated?

A

Value of the units changes with each magnification

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

How is a mounted sample prepared?

A

Very thin
Stain appropriately
Add drop of water
Place coverslip with mounted needle

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

What is used to calibrate an eyepiece graticule?

A

Stage Micrometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How much is each unit on a stage micrometer worth?

A

10 micrometers

17
Q

What equation can be used to find the units of an eyepiece graticule?

A

(Stage micrometer units/eyepiece graticule units) x 10

18
Q

How can an eyepiece graticule be used to measure a cell?

A

Unit value calculated x units

19
Q

Why are samples kept ice cold in ultracentrifugation?

A

Slow/stop enzyme activity so organelles are not digested

20
Q

Why are samples kept in a buffer solution in ultracentrifugation?

A

Keep pH the same so enzymes are not denatured

21
Q

Why are samples kept in isotonic solution in ultracentrifugation?

A

So there is no movement of water in/out and causes lysis

22
Q

What does ultracentrifugation separate organelles based on?

A

Weight/mass

23
Q

What is used to spin samples in ultracentrifugation?

A

Centrifuge

24
Q

What speed is used first in ultracentrifugation?

A

Slower

25
Q

What are the organelles at the bottom of a centrifuge called?

A

Pellet

26
Q

What is the remaining liquid in a centrifuge called?

A

Supernatent

27
Q

What is the first organelle to be separated in a centrifuge?

A

Nucleus as its the heaviest

28
Q

What is the second organelle to be separated in a centrifuge?

A

Mitochondria

29
Q
A

AQA Biology (35 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions