Microscopy Flashcards
What’s the maximum magnification of a light microscope?
x1500
How does a light microscope produce an image?
Relies on the visible part of the electromagnetic spectrum.
Are the images on a light microscope in colour?
Yes
Are the images on a light microscope 2D or 3D?
2D
What is the resolution of a light microscope?
200nm (limited)
What is the maximum magnification on a Scanning Electron Microscope?
x2 million
How does a scanning electron microscope produce an image?
Uses beams of electrons, scans the surface of the sample.
Are the images of a scanning electron microscope in colour?
No
Are the images on a scanning electron microscope 2D or 3D?
3D
What is the resolution of a scanning electron microscope?
0.4nm
What is the maximum magnification of a transmission electron microscope?
x50 million
How does a transmission electron microscope produce an image?
uses a beam of electrons which pass through the sample.
Are the images on a transmission electron microscope in colour?
no
are the images on a transmission electron microscope 2D or 3D
3D
what is the resolution of the images on a transmission electron microscope?
> 0.4nm
What are the limitations of Electron Microscopes
> the samples must be in a vacuum (the sample will be dead)
the specimens must be stained.
TEM sample needs to be thin so the electron can pass through.
SEM has a lower resolving power than TEM, however both have a higher resolving power than a light microscope
the images are in black and white.
Who developed the microscope in 1590 and what did they do?
Hans and Jansen, they created the compound microscope, it was magnified but the images were blurry.
Who developed the microscope in 1665 and what did they do?
Hooke, developed the compound microscope and described the cells in a cork.
Who developed the microscope in 1673 and what did they do?
Anton Van Leewenhoek, without knowing it he observed the first living cells.
Who developed the microscope in 1833 and what did they do?
Robert Brown, discovered the cell nucleus.
Who developed the microscope in 1838 and what did they do?
Matthios Jakob, worked with another scientist, then compared plant and animal cells and made the cell theory.
What is the cell theory?
The cell theory has 3 tenants:
-all living organisms are made of one or more cells.
-cells are the basic structural units of all organisms
-all cells originate from pre-existing cells
Who developed the microscope in 1852 and what did they do?
Robert Remak, observed cell division, however his theory wasn’t accepted by society until after 1855
Who developed the microscope in 1860 and what did they do?
Louss Pasteur, disproved spontaneous generation.
