Biology AQA 3.1.3 Cells

Structure of an epithelial cell from the small intestine.

Prokaryote: Before nucleus

Transmission Electron Microscopes
Electrons are fired onto the specimen which then absorbs electrons. this then causes an image to be produced on a screen
*The whole thing must be in a vacuum
*A complex staining process
*Image is black and white
* Specimen must be thing
*Image might contain artefacts

Magnification:

Magnification= Size of image/ size of object

M= I/o (MILO)

Cell Fractionation:
the process where cells are broken up in a c cold, isotonic and buffered solution.

Ultracentrifugation:
Process by which fragments are seperated.