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Describe the sequence of events that occur during DNA replication.

DNA replication begins with the unzipping of the double stranded DNA by the enzyme DNA helicase, which breaks hydrogen bonds as it separates the strands. Another enzyme known as topoisomerase holds the tw...

Answered by Sumrah N. • Biology tutor

22449 Views

Find the coefficient of x^4 in the expansion of: x(2x^2 - 3x + 1)(3x^2 + x - 4)

Only the terms which will form the x⁴ term need to be considered:x * 2x² * x + x * -3x * 3x² = -7x⁴Therefore the answer is -7.

Answered by Finn H. • Maths tutor

4398 Views

An object of mass 3kg is held at rest on a rough plane. The plane is inclined at 30º to the horizontal and has a coefficient of friction of 0.2. The object is released, what acceleration does the object move with?

We need to use Newtons law F=ma going down the slope.
We can see that the only forces acting in this direction are the component of the weight and friction, so we have that: F = Wsin30 - μR = 3a

Answered by Asha D. • Maths tutor

3041 Views

Describe how a stationary wave is formed at a boundary?

A stationary wave is a wave formed by the superposition of two progressive waves. These waves must have equal amplitude frequency and speed. They must also be travelling in opposite directions. When a wav...

Answered by Oliver E. • Physics tutor

4966 Views

Describe how action potentials are initiated and transmitted within a neurone, mentioning the appropriate ions and types of ion channels

A stimulus causes a small influx of sodium ions into the cell, leading the cell to become more depolarised or more positive. If this reaches the threshold potential, of about -55 mV, then it will initiate...

Answered by Roxanne M. • Biology tutor

2383 Views