Module 2.1 Microscopy

Question 1

What makes up a compound microscope

Answer 1

The objective lens which is placed near to the specimen, and an eyepiece lens, through which the specimen is viewed.

Question 2

What does the objective lens do

Answer 2

Produces a magnified image which is magnified again by the eyepiece lens

Question 3

Explain dry mount

Answer 3

Solid specimen viewed into thin slices- sectioning.

Specimen placed on slide and cover slip placed on top

Question 4

Explain wet mount

Answer 4

Specimens suspended in liquid.

Cover slip placed on from an angle

Question 5

Explain squash slides

Answer 5

Wet mount first prepared then lens tissue gently presses down the cover slip

Question 6

Explain smear slides

Answer 6

Edge of slide smears sample, creating a thin even coating on another slide- cover slip placed on top

Question 7

How do you prepare a sample for staining?

Answer 7

It is placed in a slide and air dried. It is then heat fixed by passing through a flame

Question 8

Explain gram stain technique

Answer 8

Separates bacteria into positive and negative gram bacteria

Question 9

What is a counterstain

Answer 9

Safranin dye

Question 10

Explain acid-fast technique

Answer 10

Differentiates species of mycobacterium from other bacteria

Question 11

Define magnification

Answer 11

How many times larger the image Is than the actual size of the object being viewed

Question 12

Define resolution

Answer 12

The ability to distinguish between two separate objects

Question 13

Disadvantages of electron microscopy

Answer 13

Expensive
Controlled environment
Specimens can be damaged and must be dead

Question 14

How do TEM work

Answer 14

Beam of electrons through a specimen are focussed to produce image

Question 15

How do SEM work

Answer 15

Beam of electrons over specimen surface and reflected electrons collected

Question 16

What are artefacts?

Answer 16

Visible structural details caused by processing the specimen and not a feature of the specimen itself.

Question 17

How many components in eukaryotic animal cell?

Answer 17

14

Question 18

What are prokaryotes

Answer 18

Single celled organism with a simple structure of just a single undivided internal area called the cytoplasm.

Question 19

What are eukaryotes?

Answer 19

Make up multicellular organisms like animals, plants and fungi. They contain a membrane bound nucleus and cytoplasm, which contains membrane bound cellular components

Question 20

What is metabolism

Answer 20

Involves both the synthesis and the braking down of molecules

Question 21

Magnification equation

Answer 21

Image size / object size

M = I/A

Question 22

What does staining do

Answer 22

Helps reveal or distinguish different features

Question 23

Light microscopes resolution and magnification

Answer 23

200nm

x1500

Question 24

Electron microscopes resolution and magnification

Answer 24

0.2nm

x500,000

Question 25

m to mm

Answer 25

x1000

Question 26

mm to um

Answer 26

x1000

Question 27

um to nm

Answer 27

x1000

Question 28

nm to pm

Answer 28

x1000

Question 29

What does a light microscope observe?

Answer 29

Whole cells and tissues

Question 30

What do Transmission electron microscopes observe

Answer 30

Organelles

Question 31

What does laser scanning confocal microscopes observe

Answer 31

An object at a certain depth within a cell

Question 32

Graduated measuring scale on the microscope stage

Answer 32

Stage micrometer

Question 33

Two parts of a light microscope that magnify the specimen

Answer 33

Eyepiece lens

Objective lens