neurobiology

## What I do - Study nervous system structure and function - Investigate neuronal communication - Analyze neural development - Research synaptic transmission - Study brain circuits and behavior - Investigate neural disorders ## When to use me - When studying neuron structure and function - When analyzing synaptic transmission - When investigating neural development - When researching neurological disorders - When studying brain-behavior relationships - When working with neural tissues ## Key Concepts ### Neuron Structure - **Soma**: Cell body, contains nucleus - **Dendrites**: Receive signals - **Axon**: Conducts signals away - **Axon terminals**: Release neurotransmitters - **Myelin**: Insulation, saltatory conduction ### Action Potential ```python # Simplified action potential model def action_potential(V, thresholds): """ Model neuron firing. V: Membrane potential (mV) thresholds: Resting ~-70mV, firing ~-55mV """ if V < -55: return 'resting' elif -55 <= V < 30: return 'depolarization' elif 30 >= V >= -70: return 'repolarization' else: return 'refractory' # Ion channels involved channels = { 'depolarization': 'Na+ channels open', 'repolarization': 'K+ channels open', 'refractory': 'Na+ channels inactivated' } ``` ### Synaptic Transmission 1. Action potential arrives at terminal 2. Ca²⁺ influx triggers vesicle fusion 3. Neurotransmitter release into synapse 4. Binding to postsynaptic receptors 5. Ion channel opening/closing 6. Signal termination (reuptake, degradation) ### Neurotransmitters - **Excitatory**: Glutamate, acetylcholine - **Inhibitory**: GABA, glycine - **Modulatory**: Dopamine, serotonin, norepinephrine - **Neuropeptides**: Substance P, endorphins