Ch. 41 Flashcards
What is a Neuron?
A specialized cell that transmits electrical and chemical signals in the nervous system.
What are the three main parts of a neuron?
The cell body, Dendrites, and axon.
What is the function of the cell body?
Contains the nucleus and other organelles that help to maintain the neuron’s metabolism and other functions
What are dendrites?
Are branched extensions of the cell body that receive signals from other neurons or sensory receptors.
What is an axon?
A long, think extension of the cell body that transmits signals away from the cell body to other neurons or muscles.
What is myelin?
A fatty substance that covers and insulated the axon of some neurons, allowing for faster signal transmission.
What are glial cells?
Are non-neuronal cells in the nervous system that provide support and nourishment to neurons.
What are the main types of glial cells?
Astrocytes, oligodendrocytes, microglia, and Schwann cells.
What is the function of astrocytes?
Help regulate the chemical environment around neurons and provide structural support.
What is the function of oligodendrocytes and Schwann cells?
Oligodendrocytes and Schwann cells produce myelin, which helps to insulate axons and increase signal transmission speed.
What is the function of microglia?
Are immune cells in the nervous system that help to remove damaged cells or debris.
What is multiple sclerosis?
multiple sclerosis is a neurological disorder characterized by damage to they myelin sheath, which can lead to disruptions in signal transmission and a range of symptoms.
What is the resting membrane potential?
Is the electrical potential difference across the membrane of a neuron when it is at rest.
What is the threshold potential?
the membrane potential at which an action potential is triggered.
What is depolarization?
is a process by which the membrane potential become less negative, bring it closer to the threshold potential.
What is the role of voltage-gated ion channels in action potentials?
Voltage-gated ion channels are membrane proteins that open or close in response to changes in membrane potential, allowing ions to flow in or out of the cell contribute to the generation of an action potential.