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What is the series of events that occur when an action potential enters the presynaptic neuron

The membrane around the presynaptic neurone depolarises This depolarisation causes Ca2+ voltage-gated channels to open and Ca2+ influxesCa2+ causes vesicles with specific neurotransmitters to migrate to the ...
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Answered by James A. • Biology tutor
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How is gas exchange in a human facilitated?

The gas exchange of O2 and CO2 must occur between the air-filled alveoli of the lungs and our blood circulation running through our vessels. Near our lung alveoli lie capillaries coat the alveoli. The capill...
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Answered by Hosna S. • Biology tutor
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The binding of one molecule of oxygen to haemoglobin makes it easier for a second oxygen molecule to bind, explain why.

The binding of the first oxygen changes the tertiary structure of the haemoglobin. This uncovers the second binding site, allowing the second oxygen to bind.
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Answered by Abbie T. • Biology tutor
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Describe the primary, secondary, tertiary and quaternary structure of proteins.

Primary The amine group of one amino acid reacts with the carboxyl group of another during a condensation reaction to form a peptide bond. The products of this reaction are a dipeptide and a water molecule. ...
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Answered by Hannah D. • Biology tutor
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What is the difference between DNA, mRNA and tRNA? and why are they different?

DNA, tRNA and mRNA are all essential macromolecular biological molecules involved in genetics and protein production. The two major categories of genetic molecules are DNA and RNA, with both tRNA and mRNA be...
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Answered by Tristan V. • Biology tutor
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