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Bacterial Structure
Bacteria are a type of cell but they have a very unique structure and are
not very similar to other cells such as animal cells or plant cells. Though
they do have some of the properties of both.
Below is a diagram of an average bacterial cell.


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be useful to the cell. An example for this is a gene for Antibiotic
resistance. This is found within Plasmid DNA. Plasmids can be
transferred from one bacterial cell to another, if the plasmid transferred
hold a gene to cause resistance to an antibiotic then the cell it is

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prevents most substances from moving through the membrane as they
will be stopped by either the Polar or nonpolar region of the membrane.
The plasma membrane also has proteins embedded with it, such as
Proton Motive Force
The plasma membrane is also the site of Energy conservation by the…

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When classifying between Gram Negative and Gram Positive we
describe the bacteria as being either gram Negative or Positive rather
than saying the Membrane is Gram positive or negative.
Gram negative bacteria have a plasma membrane and an outer
membrane. this is a key way to identify if you have…

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The Gram Positive wall can be identified easily as it only has one
membrane, (the plasma membrane). It also has peptidoglycan but this
is far thicker in a Gram positive cell wall. There is also no periplasmic
space as the peptidoglycan is pressed against the plasma membrane.
This Peptidoglycan how…

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(NAM). The Sugar back bone is linked by tetrapeptised. This is shown

BetaLactam Antibiotics
Half of the antibiotic's we used today are Beta Lactams. This type of
antibiotics acts on the cell wall of bacteria. An example of this is the
famous Penicillin. Penicillin works by inhibiting reactions which…

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They then need to be exposed to Grams Iodine for 1 minuet and then
rinsed with water, they should both still be purple.
At this point either 95% ethanol or Acetone is washed over the cells.
The gram negative bacteria at this point will lose their colour whereas
the gram…

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Not all bacteria, but some bacteria form spores, and some bacteria only
form spores at certain times. Spores are very tolerant of extreme
conditions, such as high heat, radiation and chemicals. The Spores only
germinate when in conditions that are favourable for the bacterial cell to
begin growth.

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The sample is then incubated and allowed to grow, the colonies are
then counted.
Dry Cell Weight
Sample is taken
The sample is then desiccated (meaning dried out)
The sample is then weighed
Turbidity is the measurement of how clouds a liquid is when bacteria are
in it. When…


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