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Describe how mRNA is produced in a cell (5 marks)

Double-helix DNA strands are separated by breaking the hydrogen bonds between complementary bases. One strand acts as a template strand which complementary bases bind to (adenine to uracil, thymine to adenin...
SG
Answered by Shubham G. • Biology tutor
8297 Views

Use the addition formulas: sin(x+y)=sin(x)*cos(y)+sin(y)*cos(x), cos(x+y)=cos(x)*cos(y)-sin(x)*sin(y) to derive sin(2x), cos(2x), sin(x)+sin(y).

sin(2x)=sin(x+x) =sin(x)cos(x)+cos(x)sin(x) =2*sin(x)*cos(x); cos(2x)=cos(x+x) =cos(x)cos(x)-sin(x)sin(x) =[cos(x)] 2 -[sin(x)] 2 Now let x+y=a and x-y=b, then x=(a+b)/2 and y=(a-b)/2. Then sin(a)=sin[(a+b)/...
IS
Answered by Ioana S. • Maths tutor
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When a nerve impulse arrives at a synapse, it causes the release of neurotransmitter from vesicles in the presynaptic knob. Describe how.

The arrival of a nerve impulse at a synapse causes Ca2+ channels to open (1 mark). Ca2+ ions enter the presynaptic knob by facilitated diffusion (1 mark). The presence of Ca2+ ions causes synaptic vesicles t...
AB
Answered by Andrew B. • Biology tutor
5878 Views

How are London forces (Van Der Waals) formed?

This is the weakest intermolecular force. It is formed by the uneven distribution of electrons in a molecule which induces a dipole in the molecule (meaning a delta positive and delta negative charge forms a...
SH
Answered by Sonia H. • Chemistry tutor
4081 Views

How can I evaluate the extent to which increased competition leads to higher levels of economic efficiency?

Keeping all other factors fixed, increased competition will make the demand curve that firms face flatter due to increased elasticity of the demand. By drawing a diagram depicting a firm's costs and revenues...
RS
Answered by Rebecca S. • Economics tutor
2457 Views