What can be utilized for energy if sugars are not available?

Which of the following is the best definition of aerobic respiration? o a. the cellular process that releases energy by breaking down glucose o b. physical activity that involves the repeated motion of large muscle groups o c. physical activity that increases heart rate and breathing rate o d. the cellular process that converts solar energy to chemical energy

What kinds of molecules can pass through the cell membrane without any problem?

Why should organisms reproduce more offspring than will survive? select all that apply.