Would happen to the human population if endosperms were not a source of food.

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

The breakdown of food is accomplished by enzymes. a. physical b. chemical c. mechanical d. none of the above

How does secondary succession differ from primary succession?