You took 3 mL of a stock solution of sodium phosphate (25 mM) and mixed it with 12 mL of water to make solution A.

You then took 1 mL of a solution A and mixed it with 1 mL of water to make solution B. 

You then took 1 mL of a solution B and mixed it with 4 mL of water to make solution C.

Calculate the concentration (in mM) of sodium phosphate in each of these solutions.

5 mL of a stock solution of 250 mM Tris buffer is diluted to a final volume of 25 mL.

What is the final concentration of the diluted Tris buffer (in units of mM)?

How many micromoles (μmol) of ATP are present in 6 mL of 5 mM ATP solution?

A sample contains 700 μg of NaOH.

How many milligrams (mg) is this?

A patient has been admitted to hospital and a blood test has shown his glucose level is 45 mg per 55 mL.

Calculate the molarity (in mM, to two decimal places) of the glucose in the patient's blood.

Shown below is a DNA duplex sequence, including both the coding (top) and non-coding (bottom) strands. 

Which one of the following pairs of oligonucleotide primers would be most suitable for amplifying (by PCR) the region of this duplex shaded in yellow?

[Note: You are not expected to estimate Tm values for these primers. If they have the correct sequence to anneal in the correct position, you should assume that they will.]

Shown below are three short DNA duplexes.

What is the correct order of stability of these duplexes (from most stable to least stable)

[Note: You do not need to calculate T_m values. You should be able to determine the order of stability “by eye”.]

The image below is a helical wheel representation of part of an alpha helix (top-down view), with each amino acid a numbered circle.

Without knowledge of any R groups, non-covalent interactions between which ONE of the following pairs of amino acids will likely help stabilise the helix?

How many peptide bonds are there in the following peptide sequence?

MetCysGlySerProLeu

(Enter a number in digits with no additional characters)

Why is glycine (shown below) the only non-chiral amino acid?