Different microscopes

Question 1

What are light microscopes used to see?

Answer 1

Living specimens

Question 2

What are transmission electron microscopes used to see?

Answer 2

They are used to see organelles

Question 3

Do electrons microscopes show colour?

Answer 3

No

Question 4

What are scanning electron microscopes used to see?

Answer 4

Cell surfaces

Question 5

What are laser scanning confocal microscopes used to see?

Answer 5

An object at a certain depth within a cell

Question 6

What kind of things can LSCM be used for?

Answer 6

Can be used to track chemicals as they travel through the body

Question 7

How do light microscopes work?

Answer 7

A condenser light focusses light on the specimen

Question 8

How does a transmission electron microscope work?

Answer 8

It uses electromagnets to focus a beam of electrons
Beams are transmitted through the specimen
Denser areas absorb more electrons

Question 9

How do scanning electron microscopes work?

Answer 9

Scans a beam of electrons
The beam of electrons scans across the surface
Electrons are collected in a cathode ray tube to form an image

Question 10

How do LSCM work?

Answer 10

Laser scans a slice of the specimen
It forms an image at a particular depth
Fluorescence dye is added to the specimen

Question 11

How do you prepare a specimen in a light microscope?

Answer 11

Dry mount
Wet mount
Squash sides
Smear slides

Question 12

How do prepare a specimen for a transmission electron microscope?

Answer 12

Specimens placed in hard resin
This makes it easier to cut
Specimens are cut very thin
They are mounted and put into a vacuum

Question 13

How do you prepare a specimen for a sem?

Answer 13

Mount it to prevent it getting contaminated

Question 14

How do you prepare a specimen for a lscm?

Answer 14

Fluorescent dyes to add to specimen

To highlight all the organelles

Question 15

What is the highest magnification on a light microscope?

Answer 15

1500x or 2000x

Question 16

What is the highest magnification on a light microscope?

Answer 16

100,000x

Question 17

What is the highest magnification of a sem?

Answer 17

100,000x

Question 18

What is the highest magnification of a lscm?

Answer 18

5000x

Question 19

What is the highest resoloution in a light microscope?

Answer 19

200nm

Question 20

What is the highest resoloution in a transmisson electron microscope?

Answer 20

0.02nm

Question 21

What is the highest resoloution in a scanning electron microscope?

Answer 21

10nm

Question 22

What is the highest resoloution in a lscm?

Answer 22

200nm

Question 23

What are the advantages and disadvantages of light microscopes?

Answer 23

A

• Cheap
• Specimen can be alive
• Easy to use

D

• Low resolution
• Can not see organelles
• Specimens must be thin

Question 24

What are the advantages and disadvantages of a TEM?

Answer 24

A

• Internal structures
• High resolution
• High magnification

D

• Specimens must be dead
• Expensive and rare

Question 25

What are the advantages and disadvantages of a SEM?

Answer 25

A - 3D Detail - False colour can be added - Materials can be thicker D - Specimens must be dead - Black and white messages

Question 26

What are the advantages and disadvantages of a lscm?

Answer 26

A - Living or dead specimens - High thickness range D - Lower resoloution

Question 27

What stains are used inside the cytosol?

Answer 27

Crystal violet or methylene blue - they are positively charged and are attracted to the negative organelles in the cytosol

Question 28

What stains are used outside the cytosol?

Answer 28

Nigrosin or Congo red