4 mechanism of intercellular communication to preserve homeostasis

  1. direct communication

    • gap junctions

    • ions, small solutes, lipid-soluble materials

    • limited to adjacent cells of same type

  2. paracrine communication

    • extracellular fluid

    • paracrine fluid

    • limited to local areas

  3. synaptic communication

    • across synapses

    • neurotransmitter

    • limited to a very specific area (axon→dendrite)

  4. endocrine communication

    • bloodstream

    • hormones

    • distance

  • hormone- chemical messengers that travel through the bloodstream to exert their effects on target cells

  • target cells- unique cellular receptors that respond to hormones

  • endocrine glands- ductless glands that produce hormones to secrete directly into bloodstream

  • endocrinology- scientific study of hormones and the endocrine organs