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The DNA polymerase in GoTaq works best when primers are present at concentrations ranging from 100 nM to 1 µM. Primers are often purchased as dry powders. Researchers typically dissolve these primers in water to make stock solutions of 5 to 50 µM, then they use these stock solutions to set up PCR reactions. In this exercise you will plan to set up a PCR reaction using this approach, by answering the following questions in the table below. Beware: When students make mistakes with these kinds of calculations, it is often due to confusion about units. Make sure you have converted all of the numbers into the correct units! Fill in the answers to these questions in the table below, rounding your answers to whole numbers (no decimal places) using the units required by the table. If the company provided you with 0.3 mg of each primer: 1: How many micrograms of each primer would you receive? 2: How many nanomoles of each primer would you receive? 3: How much water (in ml) would you dissolve each primer in to make a 10 µM stock? 4: How many microlitres of these stock solutions of each primer would you need to include in a 60 μl reaction to achieve a final concentration of 500 nM in the PCR reaction? Primer forward reverse Molecular weight (kDa) 15 10 Micrograms (ug) provided Question 1 ug ug Nanomoles (nmol) provided Question 2 nmol nmol Millilitres (ml) water to dissolve powder in to make stock solution Question 3 ml ml Microlitres (ul) of the primer stock to use in the reaction Question 4 ul ul