BIO210Y5 Study Guide - Final Guide: Adenylyl Cyclase, Thyroid, Sella Turcica
Document Summary
Direct communication occurs between two cells of the same type in extensive physical contact between the two cells. Gap junctions: coordinate ciliary movement among epithelial cells, coordinate the contraction of cardiac muscle cells, facilitate the propagation of action potentials from one neuron to the next at electrical synapses. Paracrine communication: use of chemical messengers to transfer information from cell to cell within a single tissue chemicals involved are called paracrine factors/local hormones. Paracrine factors enter the bloodstream but concentrations are usually so low that they distant cells and tissues are not affected some paracrine factors have primary effects in their tissues/organs and secondary effects on other tissues/organs. Hormones: chemical messengers that are released in one tissue and transported in the bloodstream to alter the activities of specific cells in other tissues. Nervous system does not send messages via bloodstream; neurons release neurotransmitters instead synaptic communication. Endocrine cells: glandular cells that release their secretions into the extracellular fluid.
