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Describe what happens when a nerve impulse arrives at a synapse.

A synapse is a junction between a neurone and the next cell. When an action potential arrives at the presynaptic membrane, voltage-gated calcium ion channels open. Calcium ions (Ca2+) diffuse into the synapt...
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Answered by Sophia G. • Biology tutor
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Cellular structure of the brain

The cellular structure of the brain is a relatively recent discovery and it's Santiago Ramòn y Cajal that recognised it; in addition to this he recognised the neuron as the basic unit. Three main elements ca...
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Answered by Sara D. • Biology tutor
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How is a specific protein formed from DNA?

You need to have some basic knowledge of nucleotide structure before trying to understand the answer below. First of all, DNA contains thousands of genes. Each gene codes for specific proteins (The ‘code’ me...
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Answered by Cheri C. • Biology tutor
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Compare and contrast stabilising selection with disruptive selection

They both change the allele frequency, and both select against less well adapted phenotypes. Extremes are eliminated in stabilising selection, whereas intermediates are eliminated in disruptive selection. St...
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Answered by Elizabeth T. • Biology tutor
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How does a point mutation in the gene coding for ATP synthase affect oxidative phosphorylation

In a point mutation, a single base is substituted, inserted, or deleted. This changes the sequence of amino acids in ATP synthase. This changes the tertiary structure of ATP synthase. ATP synthase is used in...
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Answered by Elizabeth T. • Biology tutor
3091 Views