An example of a grad-school level question?
Naturally occurring variations within a species are mainly the result of mutations and

An example of a grad-school level question?
Which of the following animal features most helps the animal move around in its habitat?

An example of a grad-school level question?
Which sentence describes a characteristic of offspring produced by sexual reproduction?

An example of a grad-school level question?
Jake is testing how light affects plant growth. He grows two plants in identical pots with the same amount of water and fertilizer. Jake grows one of the plants in the sun, and the other in the shade. Which part of Jake's process indicates that there is a control for this investigation?