A friend of yours appears to have put on a lot of muscle very quickly. At the same time, you notice that your friend seems to have a lot of mood swings and appears depressed. It is reasonable for you to suspect that your friend has begun to take ________.

The four most common elements found in living organisms are ________.

Nucleic acids are polymers of ________ monomers.

If one strand of a DNA double helix has the sequence AGTACTG, what will be the sequence of the other strand?

An atom with an electrical charge is a(n) ________.

How do hypotheses differ from theories?

Which of the following are the proper components of the scientific method?

Which of the following elements, essential to life, is a trace element?

A protein’s function is most dependent on its ________.

The hydrogen and oxygen atoms of a water molecule are held together by ________ bonds.