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What is the sequence of events involved in transmission across a cholinergic synapse

For transmission across the synapse to be initiated, an action potential must arrive at the pre-synaptic knob and open voltage- gated ion channels. Once the channels are open, calcium ions are able to diffus...
ES
Answered by Ellen S. • Biology tutor
14474 Views

how does the chemical structure of amino acids lead to variable physical structures of proteins

Amino acids are made up of an amine group, a carboxyl group, a hydrogen and a variable group (often noted as R) all bound to one Carbon. These amino acids can bind to one another by the amine group and the c...
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Answered by Adam B. • Biology tutor
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How to go about writing an essay in A level biology (for exampe: The importance of proteins in the control of processes and responses in organisms)

When attempting an essay question like this it is important to pull together topics from different areas of the course. Start by writing a quick plan including 5 relevant topics that you feel confident talki...
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Answered by Elys H. • Biology tutor
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Describe the types of movement of substances across a partially permeable membrane

Facilitated diffusion - the movement of substances down a concentration gradient via a membrane protein. Active transport - the movement of substances against a concentration gradient which requires energy/A...
RT
Answered by Rachael T. • Biology tutor
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Explanation of the lac operon, based on 9700/41/M/J/18 Question 3

It is made up of 3 genes: lacZ, lacY and lacA which encode for B-galactosidase (LacZ), lactose permease (LacY), and another enzyme (not studied at A level) respectively.The functions of LacZ (the enzyme) is ...
JV
Answered by Jose V. • Biology tutor
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