【文章內容簡介】
Long axons (longest from the cortex to the tip of spinal cord, 5070 cm) 2. Golgi type II Neurons ? Short axons (shortest axons terminate only a few micron from cell body, interneurons) 3. Amacrine Neurons ? An unusual cell type, lack axons –Sensory neuron ? from receptor to CNS。 receive stimuli and transmit afferent impulses to CNS –Interneurons ? municating between neurons。 form circuits in the CNS –Motor neuron ? from CNS to effector cells。 deliver efferent impulses out through the PNS to the effectors to carry out the actions directed by the CNS Functional Classification of Neuron ? EXCITABLE Membrane: Able to regulate the movement of ions (charges) across and along membrane SIGNAL TRANSDUCTION ? DO NOT Replicate: Damaged cells cannot be replaced! Important Features of Neurons Action Potential Four Functional Regions of Model Neurons ? Impulse transmission : – electrical – chemical ? Morphology : – axodendritic – axonsomatic – axoaxonic – dendrodendritic Classification of Synapses synapse 4 Vesicles release Neurotransmitters ? Chemical synapse : – presynaptic knob (presynaptic ponent) ? synaptic vesicles – synaptic cleft – postsynaptic membrane (postsynaptic ponent) ? Electrica