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Explain how a synapse between two neurons functions

When impulse arrives at pre-synaptic terminal, the depolarisation opens the voltage-gated Ca2+ ion channels. This causes Ca2+ to enter synapse due to differences in concentration. This causes the vesicles to...
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Answered by George B. • Biology tutor
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What is the difference between transcription and translation?

Transcription - involves making mRNA from DNA. It happens inside the nucleus Translation - using the mRNA as a set of instructions to make a polypeptide. Happens at the ribosome. More in depth transcription....
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Answered by Lauren M. • Biology tutor
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Explain why the atrioventricular valves open and close during the cardiac cycle.

Pressure is related to volume, and a larger volume means a lower pressure. The pressure in the atria is low initially as it is relaxed (diastole). Blood flows from high to low pressure, and this means that t...
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Answered by Ellie C. • Biology tutor
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How is immunity reached after a vaccine is given? Include the roles of both T cells and B cells.

The vaccine contains either dead or attenuated pathogens, or they can contain just antigens from the pathogen. When one is injected with a vaccine the white blood cells within the body are able to recognise ...
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Answered by Chizara L. • Biology tutor
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How does osmoregulation occur in the kidney?

The tubule fluid enters the collecting duct (CD) where the final water reabsorption occurs before the fluid is excreted as urine. Osmoreceptors in the hypothalamus detect the concentration of the blood (wate...
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Answered by Kelly D. • Biology tutor
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