Hormones are best described as

  • A. enzymes that speed up metabolism
  • B. waste products of the endocrine glands
  • C. chemical messengers carried in the blood to target organs
  • D. electrical signals sent along nerves

Explanation

Endocrine glands secrete hormones directly into the blood, which delivers them everywhere, but only cells with the right receptors respond. This slow, widespread chemical signalling complements the fast, wired signalling of the nervous system.

Related questions