"He was awakened in the middle of the night by a low growling that sounded as if it was coming from just outside his tent. In response, the cells of his adrenal medulla began to secrete epinephrine, causing his palms to sweat, his heart to race, and his hair to stand on end." Epinephrine is involved in what type of signaling as described in this passage

A. Autocrine
B. Paracrine
C. Juxtacrine
D. Endocrine
E. Contact Mediated

Which are forms of nitrogen that are usable by humans

Which group is noted for the independence of gametophyte and sporophyte generations from each other? a) ferns b) mosses, hornworts, and liverworts c) charophytes d) angiosperms e) gymnosperms

Which best compares habitat and niche? o niche is a place in which organisms live, and habitat is the way in which an organism fits into its habitat.o habitat is a place in which organisms live, and niche is the way in which an organism fits into its habitat.habitat is a group of organisms that live in an area, and niche is a specific species that lives in that areao niche is a group of organisms that live in an area, and habitat is a specific species that lives in that area.