Microscopy

What is magnification

How much bigger an image appears compared to the original object

What is resolution

Ability to distinguish between two objects in a specimen

Why are optical microscopes still popular

Cheap, easy to use, portable, study living specimens

What is the highest magnification of a light microscope

X2000

In TEMs does the beam of electrons pass through the specimen

Yes

What type of image does a TEM produce

2D black and white

What is the magnification of TEMs

2 million

Do electrons pass through the species in a SEM

No

What do electrons do in an SEM

Cause secondary electrons to bounce off the specimens surface and be focused onto a screen

What type of image does an SEM produce

3D black and white (but can add colour)

Why are electron microscopes not common

Expensive, large and require training to use

What does acetic orcein bind to

DNA

What does acetic orcein stain, to what colour

Chromosomes, dark red

What does eosin stain

Cytoplasm

What does Sudan red stain

Lipids

What does iodine stain

Cellulose, starch granules

What is the maximum resolution of SEM

3-10 nm

What is the maximum resolution of TEM

0.5 nm

Which stain would be chosen to bond to the phosphate group of DNA to make chromosomes more visible when using light microscope

Methylene blue - a positively charged dye

What does Nile blue stain

Nuclei