Neurons and Neuronal Interfaces

Study Notes

Neurons

The cerebral cortex contains approximately 20-25 billion neurons.
Neuron cell bodies come in pyramidal and stellate shapes.
Neuron cell bodies contain cytoplasm, a nucleus, and a nucleolus.
Dendrites receive information from other neurons.
Many neurons in the cerebral cortex, thalamus, and hippocampus have dendrites.
45 order dendrites show growth during learning, but are missing in Down's Syndrome individuals.
Most neurons have only one axon.
Axon width ranges from 1-4 micrometers.
Axons contain axoplasm.
Neurotransmitters are mostly released from axon terminals.
Most axons are myelinated.
Axons in the peripheral nervous system (PNS) are covered by neurilemma, allowing for better recovery after damage.

Neuronal Interfaces

Gap Junctions: occur when membranes are less than 2 nanometers apart.
Synapses: interfaces between axon terminals and dendrites, somas, or axons.
Synapses are approximately 10-15 nanometers apart.
Many drugs mimic or compete with neurotransmitters at synapses (e.g., LSD competes with serotonin).

Neuronal Classification

Unipolar cells have one process.
Bipolar cells have two processes.
Multipolar cells have three or more processes.

Glial Cells

Glial cells outnumber neurons 5-10 to 1.
Glial cell processes are interconnected in a vast syncytium primarily composed of junctions.
Types of glial cells include astroglia, oligodendroglia, and microglia.

Description

Explore the fascinating world of neurons and their interfaces through this quiz. Learn about the structure, function, and types of neurons, as well as the mechanisms of communication between them. Test your knowledge on essential topics like dendrites, axons, and synapses.