Cells key words Flashcards
The number of times bigger the image/drawing is compared to the object/real size
Magnification
The minimum distance needed to differentiate between 2 adjacent objects
Resolution
Micrometer
1x10^-6m
Nanometer
1x10^-9m
A type of microscope which has a condenser, objective lens and eyepiece lens and light is passed through the thin specimen and up through the objective and eyepiece lenses to the eye
Light microscope
Beams of electrons are used to visualize structures in a vacuum. Electrons have a smaller wavelength than light so electron microscopes have a higher resolution than light microscopes
Electron microscope
A type of electron microscope which bounces beams of electrons off the surface of an object to develop a 3D image of the specimen (no need therefore for thin sections)
Scanning electron microscope (SEM)
A type of electron microscope which asses a beam of electrons through a very thin section of specimen (which often has been stained with heavy metals to show up the fine internal structures)
Transmission electron microscope (TEM)
The process where cells are broken up and the different organelles they contain are separated out
Cell fractionation
The first stage of cell fractionation when cells are broken up by a homogeniser (blender) and organelles are released from the cell
Homogenation
The second stage of cell fractionation when the fragments in filtered homogenate are separated in a machine called a centrifuge
Ultracentrifugation
A series of lines on a microscope which can be used to calculate the size of objects
Graticule
A cell that has a membrane-bound nucleus and chromosomes. The cell also possesses a variety of other membrane-bound organelles, such as mitochondria and edoplasmic reticulum
Eukaryote
A part of a cell
Organelle
Organelle which contains the hereditary material (DNA) which codes for the synthesis of proteins in cytoplasm
Nucleus