All energy in an ecosystem continues to circulate within the same ecosystem, making it a closed system. True or False?

Awater molecule is polar because there is an uneven distribution of these between the oxygen and hydrogen atoms.

Epinephrine is a hormone released from the adrenal gland of the body, most often in a stressful situation. it is known as the "fight-or-flight" hormone. one way that it causes a response in the body is to activate receptors on muscle cells. where are these cellular receptors located? a. on the cell membrane b. in the nucleus c. on the cell wall d. around the mitochondria

Which is an example of a decomposer? a. bear b. algae c. grass d. bacteria d bacteria