Nervous system intro, neurons Branches of nervous system (generally .pdf
- 1. Nervous system intro, neurons Branches of nervous system (generally speaking) Neuron abilities Neuron organization-know whats special about all these components and how they fit together. See details of AP and Synaptic communication Dendrites Soma Hillock Axon In MN: myelination and nodes of ranvier Terminals EPSPs and IPSPs Receptors, ions involved, change in membrane potential Compare properties with APs! How summed, initiate AP AP Know different phases, ion channels involved, direction of current, effect on Vm, and stimulus for onset/off of different phases AP continued and Start Synapse Be fluent in concepts and mechanisms regarding Self propagation Unidirectional movement All or nothing amplitude Saltatory conduction - why and benefits Refractory period Absolute - inactivation 2 semi- independently regulated parts of Na channel Relative -hyperpol Solution Please find the answer below. Lec 10: 1. The nervous system is divided into the central nervous system and peripheral nervous system. 2. The basic function of a neuron is to receive the information and send a signal to other neurons, muscles, or glands. First, a neuron receives information from the external environment or from other neurons. Then, the neuron integrates, or processes the information from all of its inputs and determines whether or not to send an output signal. 3. The dendrites and axon are thin cytoplasmic extensions of the neuron. The dendrites, which branch out in treelike fashion from the cell body, are specialized to receive signals and transmit them toward the cell body. The single long axon carries signals away from the cell body. The cell body (soma) is the enlarged portion of a neuron that most closely resembles other cells. Nodes of Ranvier are a gap in the myelin sheath of a nerve, between adjacent Schwann cells. 4. Ion channels and direction: As an action potential travels down the axon, there is a change in polarity across the membrane. The Na+ and K+ gated ion channels open and close as the membrane reaches the threshold potential, in response to a signal from another neuron. At the beginning of the action potential, the Na+ channels open and Na+ moves into the axon, causing depolarization. Repolarization occurs when the K+ channels open and K+ moves out of the axon. This creates a change in polarity between the outside of the cell and the inside. The impulse travels down the axon in one direction only, to the axon terminal where it signals other neurons.