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How does an action potential travel from one neurone to another?

The action potential arriving at the presynaptic membrane causes the voltage gated calcium ion channels on the presynaptic membrane to open. This causes an influx of calcium ions into the presynaptic neurone...
GT
Answered by Gemma T. Biology tutor
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f(x)=2x+c, g(x)=cx+5, fg(x)=6x+d; c and d are constants. Work out the value of d

f(g(x))=2(cx+5)+c fg(x)=2cx+10+c 2cx=6x 2c=6 c=3 10+c=d d=13
IB
Answered by Imogen B. Maths tutor
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Make x the subject of 3y + 2x = 6y - x/2

Multiply whole equation by 2 6y + 4x = 12y - x Take 6y from both sides 4x = 6y - x Add x to both sides 5x = 6y divid both sides by 5 x = 6/5(y)
BP
Answered by Ben P. Maths tutor
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Differentiate: f(x)=(ax^2 + bx + c) ln(x + (1+x^2)^(1/2)) + (dx + e) (1 + x^2)^(1/2). Hence integrate i) ln(x + (1 + x^2)^(1/2)), ii) (1 + x^2)^(1/2), iii) x ln(x + (1 + x^2)^(1/2)).

Differentiate equation: f'(x) = (2ax + b) ln(x + (1+x^2)^(1/2)) + ((a + 2d)x^2 + (b + c)x + (c+d)) (1 + x^2)^(-1/2). Select correct values for constants to get: i) x ln(x + (1+x^2)^(1/2)) - (1 + x^2)^(1/2) +...
ME
Answered by Morgan E. STEP tutor
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Explain how Giraffes may have evolved to have long necks.

There would be variation in the length of necks in the early giraffe population. Those who had longer necks would have an advantage for survival as they would be able to reach higher into the trees to feed. ...
IB
Answered by Imogen B. Biology tutor
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