How do you know if you have a crush on someone quiz?

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

An animal cell (left) and a plant cell (right) are shown. which organelle, labeled x in the diagram, is found in both plant and animal cells?

Development has provided electrically for less money but what may be considered a cause of nuclear power