Atom A and Atom B have the same number of protons and neutrons, but they do not have the same number of electrons.

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

What are transitions between a liquid and gas called? identify which way they are transitioning