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Explain how HIV infects the body once it has entered the host

HIV is a retrovirus that infects specifically T helper cells / CD4 cells in the body.the glycoprotein (envelope protein) on the surface of the virus is able to bind to receptors on CD4 cells, and causes t...

Answered by Xiaobo (Ivy) J. • Biology tutor

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give two features of DNA that is important for DNA replication

complementary base pairing - new strand can be synthesised based on the base sequence on the template strand, so that the resulting strand synthesised is identical to the coding strand.
hydrogen bon...

Answered by Xiaobo (Ivy) J. • Biology tutor

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Given f(x) = 7(e^2x) * (sin(3x)), find f'(x)

f(x) = 7e^2x sin(3x) Chain rule: f(x) = uv → f'(x) = u'v + uv' u = 7e^2x u' = 14e^2x v = sin(3x) v' = 3cos(3x) f'(x) = 14e^2xsin(3x) + 7e^2x 3cos(3x) f'(x...

Answered by Chris K. • Maths tutor

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Differentiate y=x^3+ 7x-ln(2)

Dy/dx=3x²+7

Answered by Shrey J. • Maths tutor

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State and explain the general trend in the first ionisation energies of the Period 2 elements Lithium to Fluorine.

The general trend is that the first ionisation energies increase across the period.First ionisation energies increase across the period as from Lithium to Fluorine the nuclear charge is increasing yet the...

Answered by Alice M. • Chemistry tutor

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