BIOL 2160 Chapter : Chapter 7 Neurons
Document Summary
Chapter 7 nerve cells & electric signaling: organization of the nervous system fig 7. 1 focus on output. Sensory or afferent: conduct impulses from receptors to cns. Motor or efferent: conduct impulses out of cns to effector. Association or interneurons: located entirely within the cns. Axon hillock: where axon originates and action potentials initiated. Synapse: space between a neuron & another cell. Leak channels: always open, throughout the neuorn, resting membrane potential. Ligand-gated channels: open or close in response to, dendrites & cell body, synaptic potentials. Voltage-gated channels: open or close in response to change in membrane potential. Sodium and potassium channels: throughout, but more in axon (especially in axon hillock, action potentials. Functional classes of neurons fig 7. 4 only effector organ. May secrete epo(usually produced by kidney) for increased oxygenation of brain. Maintain normal electrolyte composition of isf in cns. Protect neurons against toxic substances and oxidative stress.
