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Topic 1- Cell Structure
Organelles of a Eukaryotic Cell
Nucleus- Cytoplasm-
Largest organelle. Solution within cell membrane.
Surrounded by nuclear envelope- double membrane with Contains enzymes for metabolic reactions.
nuclear pores. Contains sugars, salts, amino acids and nucleotides.
Nucleoplasm full of chromatin. Endoplasmic Reticulum-
Nucleolus- dense region of chromatin involved…

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Cell Fractionation
Used to extract organelles from cells.
Extracts undamaged, intact organelles.
Differential centrifugation most common method.



1. Tissue sample cut in a cold, buffered, isotonic solution.
2. Sample homogenised, cell organelles remain intact.
3. Homogenised suspension filtered to remove fat, connective tissues, cell walls etc. producing a cell free…

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Light Microscopes-
Visible Light used to illuminate specimens.
Image magnified using lenses.
Light source either a lamp or a mirror.
Specimens often need to be stained to show up.




Pros-
Can view living specimens.
Produces colour images.
Video images possible.
Simple.
Cheap.
Magnification up to 1000X

Cons-
Poor resolution.
Can't…

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Cons- Cons-
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