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How do you expand brackets?

Let's have a look at a pair of brackets: (a+b)(c+d)To expand these brackets each value in one bracket must be multiplied by all values in the other bracket separately then added together. So we have: ac+a...

Answered by Phoebe B. • Maths tutor

3108 Views

Explain the Cardiac Cycle

Deoxygenated blood from the body drains into the right atrium of the heart through the superior and inferior vena cava blood vessels. The blood then travels from the right atrium, through the tricuspid va...

Answered by Simi P. • Biology tutor

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Mutations of a DNA sequence could alter the expression of a gene. Describe and explain the process of gene expression and how a mutation could lead to disease.

DNA is a universal code for all living beings known to man. There are four nucleotide bases in DNA and RNA, the combinations of these sequences are what determine the order and length of a polypeptide. Ev...

Answered by Omar S. • Biology tutor

2369 Views

Chlorine, 15 g, is contained in a vessel with a volume of 0.80 dm3 at 330 K. Calculate the pressure exerted when the chlorine is treated as a perfect (ideal) gas giving your answer in terms of kPa

PV=nRT V=0.8 dm³=0.8 x 10^-3 m³P= nRT/V R= 8.31 J K^-1mol^-1T= 330 K n= mass/mr n = 15 g/ (2x35.5 g mol^-1) n = 0.212 mol P = (0.212 mol x 8....

Answered by Harry G. • Chemistry tutor

2511 Views

How can natural selection and isolation lead to speciation?

What is speciation?When a new and distinct species evolves from an ancestor speciesReproductively isolated from the ancestor/other species2. How does natural selection work?a. Population of individuals, w...

Answered by Laura P. • Biology tutor

4177 Views