In your own words, what is the definition for substrate with enzyme. can someone please help with this?

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

Hurry where is the majority of earth's water found? o glaciers o oceans ground o rivers and lakes

Plz ! what does it mean for an allele to be dominant?