1325624
Descrição
Mapa Mental por sophieisnotakise, atualizado more than 1 year ago
|
Criado por sophieisnotakise
mais de 10 anos atrás
|
|
Microscopes
- Total magnification =
Object mag. x Eyepiece
mag.
- Magnification is the degree to
which the size of an image is larger
than the object itself.
- Magnification is the degree to
which the size of an image is larger
than the object itself.
- Resolution is the degree to which
2 very close objects can be
distinguished to see the details.
- The higher the resolution,
the greater the detail of a
specimen.
- The higher the resolution,
the greater the detail of a
specimen.
- LIGHT MICROSCOPES
- max. resolution is 200nm
- use objective lenses that can
be rotated to view specimens
at varying magnifications
- max. magnification x1500
- Preparation of Specimens:
- #1 Staining - chemicals bind to chemicals
in/on specimen, allow specimen to be seen
- some stains bind to specific cell
structures
- #2 Sectioning - embed specimen in
wax, cut sections without damaging
their structure
- #1 Staining - chemicals bind to chemicals
in/on specimen, allow specimen to be seen
- some stains bind to specific cell
structures
- can be used to view living organisms
- relatively cheap, can view natural colour of specimens, small and protable
- relatively cheap, can view natural colour of specimens, small and protable
- max. resolution is 200nm
- ELECTRON MICROSCOPES
- Generate a beam of electrons with a wavelength of
0.004nm. Use magnets to direct the beam. Must be viewed
on a screen.
- Can distinguish between objects 0.2nm apart.
- max. resolution 0.1nm
- max. magnification x500,000
- Transmission Electron Microscopes
- beam passes through thin
specimen, pass through less
dense areas less easily
- 2D image
- x500,000 mag
- beam passes through thin
specimen, pass through less
dense areas less easily
- Scanning Electron Microscopes
- electrons bounce off specimen
- 3D image
- x100,000 mag
- electrons bounce off specimen
- specimen must be placed in a vacuum
- can only be used by highly trained personnel,
only b&w images, can view cell ultrastructure, v.
expensive
- can only be used by highly trained personnel,
only b&w images, can view cell ultrastructure, v.
expensive
- Generate a beam of electrons with a wavelength of
0.004nm. Use magnets to direct the beam. Must be viewed
on a screen.
Quer criar seus próprios Mapas Mentais gratuitos com a GoConqr? Saiba mais.