Summary
Highlights
Introduction to Neurons and Glial Cells00:00:00
The nervous system coordinates body movement and sentience via neurons. Neurons are amitotic cells with branching extensions that transmit signals, while glial cells provide structural support and protection.
Neuron Anatomy00:01:58
A neuron consists of a cell body containing organelles, dendrites for receiving signals, and an axon for transmitting electrical impulses. Many axons are myelinated by Schwann cells, which act as insulators to increase signal conduction speed.
Classifying Neurons00:04:29
Neurons are classified structurally as unipolar, bipolar, or multipolar based on their processes, and functionally as sensory (afferent), motor (efferent), or interneurons.
Membrane Potential and Action Potentials00:06:52
Electrical signals are generated by manipulating ion concentrations across the plasma membrane. An action potential occurs when depolarization crosses a threshold, propagating a signal along the axon to be released as neurotransmitters at the synapse.
Organization of the Nervous System00:11:11
The nervous system is divided into the Central Nervous System (brain and spinal cord) and the Peripheral Nervous System. The latter is further subdivided into sensory and motor divisions, with the motor division split into somatic (voluntary) and autonomic (involuntary) systems.