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Find the equation of the tangent to the curve y=3x^2-7x+5 at the point (2, 3) .

The starting point for a question like this is to differentiate the function - in this case the curve y=3x²-7x+5 . We calculate that dy/dx=6x-7 . The question tells us that we are interested i...

Answered by Matthew S. • Maths tutor

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Approximately how long is a double-stranded DNA molecule with a molecular weight of 3x10^9 g/mol? Assume the molecular weight of one nucleotide is 333 g/mol, and that there are 10 base pairs for each turn of the DNA helix equalling 3.4nm in length.

Let's begin by assessing the molecule. If we divide the molecular weight by two, that will give us the weight for one strand of the helix. Knowing that one nucleotide is 333 g/mol, then dividing the wei...

Answered by Aaron V. • Human Biology tutor

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Explain how during a game of a rugby, an increase in blood Co2 will cause heart rate to rise (4 marks)

As the muscles in the body respire and use up the oxygen, Co2 is produced and thus blood acidity in the bloodstream rises
2) This change is detected by the chemoreceptors
3) These impulses...

Answered by Toby M. • Physical Education tutor

2208 Views

What is the difference between mitosis and meiosis?

Mitosis is the process used by normal body cells for everyday replication to maintain a healthy body, for example tissue regeneration. On the other hand, meiosis is the process whereby the gametes, sperm ...

Answered by Clare G. • Biology tutor

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