PSYC62H3 Lecture Notes - Lecture 3: Neuroglia, Neurotransmission, Resting Potential
Document Summary
Lecture 3: neuronal conduction and transmission and neuroactive ligands. Neurons are extremely densely packed in the cerebellum (more than in the cerebrum) Approximately 90 billion neurons in the central nervous system. About 10 to 50 times more glia than neurons. Genesis of disease states the other brain book on glia. Presynaptic cells convey information to postsynaptic cells that receive information. Axons: main conducting unit longer than dendrites can be almost 1 m in the pns. Axon hillock: area of soma where axon attaches. Area where all signals converge and cell decides whether to fire an action potential. Myelin sheath: insulating axons speeds up the rate of action potential. Nodes of ranvier: gaps between myelin sheaths where action potential jump over. Terminal branches: with terminal endings (or boutons) where the signal is passed to the adjacent cell. Synapse: gap where the first cell"s signal passes to the next cell. Two major processes involved in communication between neurons.
