Archive for September, 2012

The Mitochondria are structures or ‘Organelles’ found inside cells.
They are termed the ‘Powerhouse’ of the cell because they generate energy in order for the cell to be able to carry out its functions.
The process of energy generation is called ‘Cellular Respiration’ and involves a chemical reaction known as ‘Oxidative Phosphorylation’.  Oxidative Phosphorylation occurs on the surface of the inner membrane of the mitochondrion.
Cells which use a lot of energy, e.g. Muscle Cells have a lot more mitochondria than cells which do not require a lot of energy, e.g. Fat Cells.

The Structure of Mitochondria
The mitochondrion has two membranes, an inner membrane and an outer membrane.
The outer membrane is smooth but the inner membrane is folded – this means that there is more space (a larger surface area) for Oxidative Phosphorylation to take place.
These folds are known as ‘cristae‘.

Parts of the Mitcohondrion

Also inside the mitochondria are ribosomes (another organelle also found around the cell itself) and a ring of Mitochondrial DNA.

For interest: the mitochondrial DNA shows many similarities to bacterial DNA and differs from the DNA found in the cell’s own nucleus.  It is thought that, in evolutionary terms, mitochondria may have started out as independent creatures which set up a mutually beneficial relationship with cells of more complex organisms such as animals and plants.

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A common quandry in parasitology is identification of different types of parasites.
When it comes to the subject of lice, there are some happy coincidences which make life easier.

For Sucking Lice, simply remember the initial letter ‘S:

They Suck
They have Small heads
They move Slowly
They have Sideways or forward pointing antennae
They are around 5mm in size
(ok, stretching it but the number ‘5’ looks a wee bit like an ‘S’)

For Biting Lice, the letter ‘B‘ is all important:

A Biting Louse
They Bite
They have Big heads
They Move Bloomin’ quick (ahem!)
They have Backward pointing antennae
They are around 3mm in size
(if you draw a vertical line through the start of the number ‘3’, it becomes a ‘B’)