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How are epigenetics involved in regulating gene expression?

Epigenetic control of gene expression involves mechanisms that do not alter the sequence of DNA itself. External factors acting upon cells translate their signals via cascades to the nucleus, where they ...

HH
Answered by Harry H. Biology tutor
2965 Views

How can I use the normal distribution table to find probabilities other than P(z<Z)?

The normal distribution tables show, for a given Z value, the probability that the random variable z takes a value less than Z or P(z<Z). This is also the area under the normal distribution curve up to...

HA
Answered by Holi A. Maths tutor
4109 Views

I am finding it hard to come up with idea's during my speaking exam. How can I make the conversation flow better?

This is a problem many people deal with, so you are not alone. During oral exams, we can feel so under pressure that our minds go blank and we forget everything we learnt. There are several ways to overc...

LG
Answered by Lucie G. French tutor
1965 Views

What's the difference between the 'lock and key' and 'induced fit' models for enzymes?

The lock and key hypothesis suggests that the enzyme has a fixed shape/structure and the substrate has to fit into this exactly for catalysis to occur. The induced fit hypothesis is different in that it s...

HW
Answered by Harriet W. Biology tutor
10075 Views

Using Newton's law of universal gravitation, show that T^2 is proportional to r^3 (where T is the orbital period of a planet around a star, and r is the distance between them).

(Lets consider a simple planetary system composed of a planet orbiting a star. the gravitational force between the two is given by F=(GMm)/(r2). Assuming the planet also moves in a circular orb...

KS
Answered by Karanvir S. Physics tutor
28747 Views

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