________ are chemical messengers that are released in one tissue and transported in the bloodstream to alter the activities of specific cells in other tissues.
A) Hormones
B) Neuropeptides
C) Neurotransmitters
D) Humoral antibodies
E) none of the above

Question

Quizplus · Accepted Answer

Hormones are chemical messengers that are released from endocrine glands and are transported via the bloodstream to target cells in different tissues to regulate specific physiological processes. Neuropeptides are also chemical messengers but are found in the nervous system and act as neurotransmitters or neuromodulators. Neurotransmitters are chemical messengers that act locally in the synaptic cleft to transmit signals between neurons. Humoral antibodies are produced by B lymphocytes and are involved in the immune response. Therefore, the best choice is A) Hormones.

________ Are Chemical Messengers That Are Released in One Tissue