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Biology

A Level

What are gene mutations?

A mutation is any change to the base sequence of DNA.

The different types of mutations that can occur include:

Subsitution - this is where one base is swapped for another

Delet...

Answered by Lauren G. • Biology tutor

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What is endosymbiosis and how does it relate to mitochondria?

Endosymbiosis is where two organisms live together, one inside the other: endo=in, sym=together and biosis=living.

Answered by Aidan H. • Biology tutor

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Describe the structure of the cell membrane

The cell membrane is made up of something called the phospholipid bilayer. This is exactly what it sounds like:a hydrophilic phosphate head on the outside and a hydrophobic lipid on the inside.

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Answered by Thomas W. • Biology tutor

5156 Views

How is a message transferred across a synapse?

A synapse is a junction between the end of one neuron (known as the pre-synaptic neuron) and either another neuron (known as the post-synaptic neuron) or...

Answered by Max B. • Biology tutor

11749 Views