Microscopy

Question 1

Microscope

Answer 1

An instrument that allows you to magnify an object that may not be visible with the naked eye.

Question 2

Types of Microscopes (4)

Answer 2

Light
SEM
TEM
LSCM

Question 3

SEM

TEM

Answer 3

Scanning Electron Microscope

Transmission Electron Microscope

Question 4

Eyepiece Lens

Answer 4

x10 Magnification

Eyepiece graticule can be inserted

Question 5

Coarse-focus knob

Answer 5

Allows for quick focus

Question 6

Fine-focus knob

Answer 6

Allows for intricacy in focusing on an image

Question 7

Turret

Answer 7

Allows to switch between different objective lenses

Question 8

Objective Lens

Answer 8

x4,x10,x40

Question 9

Specimen Stage

Answer 9

Where slide is kept

Question 10

How a microscope is held

Answer 10

Arm and Base

Question 11

How an SEM works

Answer 11

A beam of electrons sent across the surface of a specimen.

Reflected electrons collected

Question 12

How a TEM works

Answer 12

A beam of electrons is transmitted through a specimen and focused to produce an image.

Question 13

How an LSCM works

Answer 13

A single spot of focused light is moved across a specimen, causing fluorescence from components labelled with a dye.
Emitted light from specimen filtered through a pinhole aperture.
Only light radiated from near to the focal plane is detected.

Question 14

Properties of a Light Microscope

Answer 14

Wavelength is longer
Resolution of 200nm
Max Magnification of x2000
Chemical Stain

Question 15

Properties of a TEM

Answer 15

shorter wavelength
Resolution of 0.2nm
Max Magnification of x2,000,000
Heavy Metal Stain

Question 16

Properties of an SEM

Answer 16

the same wavelength of TEM
Resolution of 3nm
Max Magnification of x500,000
Heavy Metal Stain

Question 17

Properties of LSCM

Answer 17

Uses Light

Allows for 3D imaging whilst object can be alive

Question 18

Light Microscope Image

Answer 18

2D
Organelles
Transparent until Stained
The specimen can be alive

Question 19

TEM image

Answer 19

2D
Organelles
Black and White unless stained
The specimen is not alive

Question 20

SEM image

Answer 20

3D
No Organelles: only Surface
Black and White unless stained
The specimen is not alive

Question 21

LSCM

Answer 21

3D
produces z sections
Colored with ‘dye’
The specimen can be alive

Question 22

Properties of Staining

Answer 22

Increases contrast within cells

Allows components to become visible

Question 23

Differential Staining

Answer 23

Used to distinguish between two types of organisms that would otherwise be hard to identify.

Question 24

Gram stain

Answer 24

Crystal violet and then iodine is applied to the slide.
Gram-positive retain the stain- purple
Gram negative do not- too thin of a cell wall- Sarafin (stain) turns pink

Question 25

Acid Fast acts on

Answer 25

Differentiates Species of Mycobacterium from other bacteria

Question 26

Acid Fast Process

Answer 26

Lipid solvent is used to carry carbolfuchsin dye. Cells washed with a dilute acid-alcohol solution. Mycobacterium not affected by wash and retain stain.

Question 27

Magnification=

Answer 27

Size of image/Actual size

Question 28

Actual Size=

Answer 28

Size of Image/Magnification

Question 29

Size of Image=

Answer 29

Magnification x actual size