What makes heart muscles contract, thereby regulating heart rate?

Aperson is outside exercising. body temperature begins to rise, and the person starts to sweat. their body temperature then returns to normal, and the body stops sweating. a positive b negative c allosteric d homeopathic

Stephen is a student who wants to test his knowledge of medical terminology. which option could he use?

Tropical rain forests support more species per unit area than any other terrestrial ecosystem. what is one way rain forests are important to the health of the biosphere?