UNIT 3 - CHAPTER 10: NERVOUS SYSTEM I, Basic Structure and Function

These flashcards cover key terms and concepts related to the basic structure and function of the nervous system, as discussed in Chapter 10.

Nervous System

A network of cells that sense and respond to stimuli to maintain homeostasis.

Neuron

The structural and functional unit of the nervous system; a nerve cell.

Neuroglia

Support cells in the nervous system that assist neurons and maintain homeostasis.

Central Nervous System (CNS)

Includes the brain and spinal cord.

Peripheral Nervous System (PNS)

Nerves that extend from the brain (cranial nerves) and spinal cord (spinal nerves).

Dendrites

Processes of a neuron that receive information and carry impulses toward the cell body.

Axon

A long, thin process of a neuron that carries impulses away from the cell body.

Myelin

A fatty substance that surrounds and insulates certain nerve fibers to facilitate faster impulse conduction.

Nodes of Ranvier

Gaps in the myelin sheath between Schwann cells that facilitate the rapid conduction of action potentials.

Synapse

The junction between two neurons where an impulse is transmitted.

Neurotransmitter (NT)

Chemical messengers that transmit signals across a synapse.

Excitatory Post-Synaptic Potential (EPSP)

A depolarization of the postsynaptic membrane, making an action potential more likely.

Inhibitory Post-Synaptic Potential (IPSP)

A hyperpolarization of the postsynaptic membrane, making an action potential less likely.

Action Potential (AP)

A rapid rise and fall in voltage or membrane potential across a cellular membrane.

Threshold Potential

The level of depolarization needed to trigger an action potential.

Afferent Neurons

Nerve cells that carry sensory impulses toward the central nervous system.

Efferent Neurons

Nerve cells that carry motor impulses away from the central nervous system.

Neuropeptides

Short chains of amino acids that act as neurotransmitters or neuromodulators.

Homeostasis

The maintenance of stable internal conditions in an organism.

Facilitation

A condition in neuronal pools where stimulation becomes easier to achieve due to increased excitation.

Convergence

When many neurons converge onto fewer neurons for summation.

Divergence

When fewer neurons spread out to stimulate many neurons, amplifying the signal.