Title Endocrine gland & Hormone.. no need.pdf ✅

Endocrine-01 Endocrine glands: name, Hormones: definition, classification, mechanism of action, regulation of secretion. 1
A chemical messenger is any compound that serves to transmit a message. The multiple activities of the cells, tissues, and organs of the body are co-ordinated by the interplay of several types of chemical messenger systems: 1. Neurotransmitters are released by axon terminals of neurons into the synaptic junctions and act locally to control nerve cell functions. 2
2. Endocrine hormones are released by glands or specialized cells into the circulating blood and influence the function of target cells at another location in the body. 3. Neuroendocrine hormones are secreted by neurons into the circulating blood and influence the function of target cells at another location in the body. 4. Paracrines are secreted by cells into the extracellular fluid and affect neighboring target cells of a different type. 3