Microscopy

Question 1

Magnification

Answer 1

how many times bigger the image produced by the microscope is than the real-life object you are viewing

Question 2

Resolution

Answer 2

the ability to distinguish between objects that are close together

Question 3

Light microscopes

Answer 3

use light to form image. there is low resolution( maximum 0.2mμ). Their magnification is maximum x1500. used to observe eukaryotic cells, nucleus, mitochondria, chloroplast.
The specimens can be alive. useful for looking at whole cells, small plants. specimen can be alive.
use fluorescent stains(specific cell structures and organelles) and immunofluorescence(antibodies, virus proteins)

Question 4

Electron microscopes

Answer 4

use electrons to form an image. much higher resolution, alot of detail (max 0.0002 µm) can observe small organelles such as ribosomes,
the rER,lysosomes. high magnification ×1,500,000.
specimen has to be dead.
Cryogenic electron microscopy(3D representation of a cell proteins)
Freeze fracture(be used to provide a unique planar view of the internal organisation of cell
membranes)

Question 5

Transmission microscopes

Answer 5

use electromagnets to focus a beam of electrons
They give high-resolution images (more detail)
This allows the internal structures within cells (or even within organelles) to be seen
They can only be used with very thin specimens or thin sections of the object being observed
They cannot be used to observe live specimens

Question 6

Scanning electron microscopes

Answer 6

scan a beam of electrons across the specimen. They can be used on thick or 3-D specimens. ○ They give lower resolution images (less detail) than TEMs cannot be used to observe live specimens and do not produce a coloured image