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This article provides an overview of neuron structure and function in the human nervous system.
Anatomy of a neuron (video) | Human biology | Khan Academy
Neurons (or nerve cells) are specialized cells that transmit and receive electrical signals in the body. Neurons are composed of three main parts: dendrites, a cell body, and an axon. Signals are received through the dendrites, travel to the cell body, and continue down the axon until they reach the synapse (the communication point between two neurons).
Overview of neuron structure (types of neurons) - Khan Academy
And these targets cells may be another neuron, they may be a muscle cell, or they may be a gland cell. A few neurons even have axons that terminate on capillaries, to secrete substances called hormones into the bloodstream.
Anatomy of a neuron - Khan Academy
A neuron can be a reasonably normal sized cell, although there is a huge range, but the axons can be quite long. They could be short. Sometimes in the brain you might have very small axons, but you might have axons that go down the spinal column or that go along one of your limbs-- or if you're talking about one of a dinosaur's limbs.
Neuron resting potential description (video) | Khan Academy
Explore the neuron resting membrane potential, a stable charge separation across the cell membrane. Discover the roles of anions and cations, and how their concentration differences create this potential. Uncover how neurons use these electrochemical driving forces to …
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The nervous system is divided into two main parts: the central nervous system, consisting of the brain and spinal cord, and the peripheral nervous system, made up of nerves and ganglia. Information travels in two directions: from the periphery to the central nervous system via afferent neurons, and from the central nervous system to the periphery via efferent neurons. This …
Structure of the plasma membrane - Khan Academy
To perform these roles, the plasma membrane needs lipids, which make a semi-permeable barrier between the cell and its environment. It also needs proteins, which are involved in cross-membrane transport and cell communication, and carbohydrates (sugars and sugar chains), which decorate both the proteins and lipids and help cells recognize each other.
Neuron action potential mechanism (video) | Khan Academy
See how action potentials in neurons are generated and conducted. Explore the role of voltage-gated ion channels and how they open when the membrane potential crosses a threshold value, as well as the influx of sodium ions and efflux of potassium ions during an action potential, and the refractory period that follows.
How neural networks work - Khan Academy
Our brains are made up of special cells called neurons. A neuron has two ends: input signals enter in on one end, they're combined together inside the neuron, and leave out the other end as a single output.
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