Describe the roles of neuromuscular junctions, the T-tubule system and sarcoplasmic reticulum in stimulating contraction in striated muscle

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Describe the structure of a cholinergic synapse and explain how it functions, including the role of calcium ions

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Explain the importance of the refractory period in determining the frequency of impulses

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Describe and explain the rapid transmission of an impulse in a myelinated neurone with reference to saltatory conduction

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Describe and explain changes to the membrane potential of neurones, including: • how the resting potential is maintained • the events that occur during an action potential • how the resting potential is restored during the refractory period

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What is the Difference between nervous system and the endocrine system?

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Explain the principles of operation of test strips and biosensors for measuring the concentration of glucose in blood and urine, with reference to glucose oxidase and peroxidase enzymes

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Explain how negative feedback control mechanisms regulate blood glucose concentration, with reference to the effects of insulin on muscle cells and liver cells and the effect of glucagon on liver cells

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Describe the principles of cell signalling using the example of the control of blood glucose concentration by glucagon, limited to: • binding of hormone to cell surface receptor causing conformational change • activation of G-protein leading to stimulation of adenylyl cyclase • formation of the second messenger, cyclic AMP (cAMP) • activation of protein kinase A by cAMP leading to initiation of an enzyme cascade • amplification of the signal through the enzyme cascade as a result of activation of more and more enzymes by phosphorylation • cellular response in which the final enzyme in the pathway is activated, catalysing the breakdown of glycogen

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Relate the detailed structure of the Bowman’s capsule and proximal convoluted tubule to their functions in the formation of urine

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