How animals can be classified on the basis of the ability to thermoregulation?

Which pattern most likely came from a gunshot and which one was produced from a blow on the head? explain your answer?

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

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )