A protein has an absorbance of 0.41, and 6 tryptophans (ε = 5500) and 4 tyrosines (ε = 1490). What is its concentration?

You have a stock of DNA ligase at 50,000 units/µl. You need 10,000 units of ligase in a 20 µl reaction, how many microliters of ligase do you need?

When using a pipette, the greatest accuracy is achieved by

The following represents a centrifuge rotor. Where should you place 5 tubes to ensure the centrifuge is properly balanced?

Which type of rotor is best to use if you wish to separate a sample into a pellet and supernatant?

You wish to study the effects of of a drug’s concentration on bacterial growth. For this experiment, you alter the drug’s concentration and measure the change in bacterial growth, while making sure the temperature is constant in each sample. Which is the control?

A group of graduate students gather every week to present papers from the latest editions of Nature. This is called a(n)

The Belmont Report requires “justice” and a “fairness in distribution”. This refers to

How do you prepare 400 ml of 70 mM Tris (Mw = 121.14)?

What would you expect absorbance of a sample to be if it had a transmittance of 26%?