3.2.1.3 Studying Cells

Question 1

What is the definition of magnification?

Answer 1

how many times bigger an object appears

Question 2

What is the definition of resolution?

Answer 2

the ability to distinguish 2 points

Question 3

Optical Microscope: magnification

Answer 3

x1500

Question 4

Optical Microscope: resolution

Answer 4

0.2 µm

Question 5

Optical Microscope: advantages

Answer 5

-image in colour
-cheaper
-can view live specimens

Question 6

Optical Microscope: disadvantages

Answer 6

-low resolution (lacks detail)

Question 7

Optical Microscope: How does it work?

Answer 7

-light waves focused on an object and onto eye, using glass lenses

Question 8

TEM: resolution

Answer 8

0.2 μm

Question 9

TEM: magnification

Answer 9

x50000000

Question 10

TEM: How does it work?

Answer 10

electromagnets focus on beam of electrons transmitted through specimen

Question 11

TEM: advantages

Answer 11

-high resolution
-high magnification

Question 12

TEM: disadvantages

Answer 12

-expensive
-time-consuming
-requires complex prep
-2D
-black and white (looks more like an artefact)
-dead cells

Question 13

TEM stands for…

Answer 13

transmission electron microscope

Question 14

SEM stands for…

Answer 14

scanning electron microscope

Question 15

SEM: resolution

Answer 15

20nm

Question 16

SEM: magnification

Answer 16

x1000000

Question 17

SEM: How does it work?

Answer 17

electromagnets focus on beam of electrons reflecting off of surface of specimen

Question 18

TEM: How do you prepare a sample?

Answer 18

-fix specimen
-dehydrate
-cut thin slices
-stain using metals
-mount outside and place in vacuum

Question 19

SEM: advantages

Answer 19

-high resolution
-high magnification
-3D image

Question 20

SEM: disadvantages

Answer 20

-expensive
-needs specialist/ lots of prep
-specimen dead
-black and white