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Electron
Scanning Electron
Microscope (SEM)
Like an MRI, SEMs take
layers of samples and then
join the sections together,
creating a 3D image.
Transmission Electron
Microscope (TEM)
Organelles
Cell Surface Membrane
Controls what goes into
and out of the cell. Controls
osmosis and diffusion.
Nucleus
Contains DNA, mRNA travels from
here through the nuclear pours to
ribosomes to synthesise protiens
Mitochondrion
Cristae
Synthesises ATP (energy)
Lysosomes
Digests unwanted cells and proteins
Ribosomes
Synthesises proteins.
Rough Endoplasmic Recticulum
Has ribosomes on the surface making its
appearance look 'rough'. Centre of all
protein synthesis.
Smooth Endoplasmic Recticulum
Manufactures lipids
Stores glycogen in the liver
Golgi Apparatus
Gathers small molecules
and turns them into
larger more complex ones.
The apparatus packages
them into vesicles and
either stores them for
later use or sends them
out of the cell.
Synthesises lysosomes (cell digestion machines)
Digests unwanted proteins
Differential Centrifugation
Homogenate
Pellets are filtered using their deffering densities
A: Blended cell, contains all organelles
B: Nucleus
C: Mitochondrion
D: Ribosomes
Isotonic
Equal water potential.
Buffer
Prevents change in pH levels.
Hypotonic
Lower concentration of salts-> high water potential
Hypertonic
High concentration of salts-> low water potential
Water Potential
Ψ
Water potential is essentially a unit of
osmosis, but water molecules do not
transfer from high concentration to low, it
is due to probability that molecules are
around the same amount on each side.
Ice Cold
Halts enzyme activity.
Prokaryotic Cells
Does not contain a membrane bound nucleus or any
membrane bound organelles
Bacteria Cells
Has a flagellum, capsule,
bacterial chromosome,
mesosomes, plasmid
DNA and a plasma membrane.
Eukaryotic Cells
Contains a nucleus and
membrane-bound organelles
Animal
No cell wall or vacuole. Only has cell membrane. Contains mitochondrion for synthesising ATP
Plant
Has a cell wall,
chloroplasts containing
chlorophyll and vacuole.