The changes that occurred in Yellowstone National Park after all of its wolves were killed showed that wolves are
A. harmful to the ecosystem
B. the only producers in the ecosystem
C. beneficial to the ecosystem
a
D. unnecessary for the survival of other species

Which of these is true for bacteria because they are prokaryotic cells? a. they can engulf body cells in order to make memory cells. b. they must invade viruses in order to reproduce. c. they are much larger than eukaryotic body cells. d. they can reproduce on their own outside of other cells.

Milk production during breastfeeding is increased by the suckling of a newborn from his mother's nipple. this type of feedback mechanism best describes a positive or negative

Oak and maple trees, chipmunks, white-tail deer, and black bears emerging from hibernation are all organisms that may be found in which biome