BIOL 1105 Lecture Notes - Lecture 6: Polyspermy, Adenylyl Cyclase, Skeletal Muscle
Document Summary
Cell signaling: signaling cell, produces and releases signal, signal molecule (ligand, target cell, uses receptor protein to detect signal and initiate response. Direct contact signaling: cells touch each other and are connected by gap junctions, fastest method of signaling, signals sent directly from the cytoplasm of one cell to another, allows cells to function as a group (cardiac muscle cells) Endocrine signaling: signal travels a long distance through the body to target cell, relatively slow (long distance, used for longer lasting responses, signal is called a hormone. Synaptic signaling: exclusively for nerve cells signal is electrical current that causes chemical neurotransmitters to be released across synaptic gap to target. Long and short distance aspects: fast transmission despite long distance, as with paracrine signaling, very brief communication, example: muscle cell contracting. This usually turns on transcription, but can also turn it off: cellular response is a change in gene expression. Common components of hydrophilic signal pathways: receptors.
