Which of the following is the best definition of an atom?

Why do we perceive objects as retaining their brightness under different lighting levels?

Which of these has happened to your food by the time it reaches your small intestine? a. all the macromolecules have been broken down completely. b. lipids and starches have been partially broken down. c. starches and proteins have been partially broken down. d. proteins and lipids have been broken down into subunits.

What term describes a doctor who becomes a specialist by meeting standards beyond those of getting a license and passing a test in the specialty area?