How many universes are scientifically proven to exist?
a) 0
b) 1
c) billions
d) infinite

The number of living organisms in a particular area is

Select all the true statements about the cosmic microwave background radiation

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