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Describe how ACh transmits nerve impulses across Cholinergic Synapse

1.AP arrives at the presynaptic neurone2.AP stimulates voltage gated Ca ion channels to open3.Increased permeability of Ca ion channels causes synaptic vesicles to fuse with presynaptic membrane4. Exocytosis...
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Answered by Natasha A. Biology tutor
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Describe the process of transcription in detail (6 marks)

Transcription is the process by which a section of DNA acts as a template for the creation of a complementary mRNA strand. mRNA is needed for the creation of a polypeptide. An enzyme called DNA helicase bind...
KH
Answered by Katherine H. Biology tutor
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Describe and explain the differences in the function of the sympathetic and parasympathetic nervous systems.

The sympathetic and parasympathetic nervous systems tend to have opposite effects on the organs which are innervated by their nerves. The Sympathetic NS innervates organs via the sympathetic chain and the pa...
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Answered by Amar S. Biology tutor
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How does oxidative phosphorylation produce ATP?

Oxidative phosphorylation requires the electron carrier system; comprised of four protein complexes (complexes I - IV) as well as the enzyme ATPase. These are intrinsic enzymes that line the inner mitochondr...
JB
Answered by Jack B. Biology tutor
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People who have McArdie's disease produce less ATP than healthy people. As a result, they are not able to maintain strong muscle contraction during exercise. Use your knowledge of the sliding filament theory to suggest why (AQA BIOL5)

Idea ATP is needed for:1. Attachment / cross bridges between actin and myosin;2. Power stroke / movement of myosin heads in rowing action / pulling of actin towards the centre of the sarcomere;3. Detachment ...
SO
Answered by Salma O. Biology tutor
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