Electron microscopes (DR)

Question 1

Electron microscopes

Answer 1

use a beam of e- with wavelengths less than 1nm to illuminate the specimen

-> allowing for greater detail of cell ultrastructure than a light microscope

Question 2

Scanning Electron Microscope
SEM

Answer 2

-A beam of e- is passed through the specimen and onto the detector at the bottom which generates an image
! the detector can be a separate tube in diagrams

X500,000 max magnification
0.5 nm resolving power
black and white image
2D
internal structures (from slices of the specimen)
specimens are dead

Question 3

Transmission Electron Microscope
TEM

Answer 3

-a beam of e- is sent onto the specimen, reflected electrons are detected by the detector which generates an image

X500,000 max magnification
3-10 nm resolving power
black and white image
3D
external structures
specimens are dead