BIO 120 Nervous System Notes

A selection of vocabulary flashcards covering key concepts from the nervous system lecture.

Nervous System

Monitors internal and external stimuli, interprets information, and maintains homeostasis.

Dura Mater

The outermost layer of the three meninges.

Arachnoid Mater

The middle layer of the three meninges.

Pia Mater

The innermost and most vascular layer of the three meninges.

Cerebral Cortex

The outer half-inch of the cerebrum made of gray matter.

Corpus Callosum

Connects the cerebral hemispheres.

Thalamus

The relay station transmitting sensory information to different areas of the cerebrum.

Reticular Formation

Helps regulate the sleep-wake cycle.

Brain Stem

Made up of the medulla oblongata, pons, and midbrain.

Medulla Oblongata

Regulates heart rate and blood vessel diameter.

Pons

Helps regulate respiration.

Cerebellum

Helps coordinate movement.

Blood-Brain Barrier (BBB)

Structure that blocks many medications from entering the CNS.

Broca’s Area

Coordinates speech.

Wernicke’s Area

Helps with understanding language.

Hypothalamus

Coordinates the autonomic nervous system and controls hunger and thirst.

Astrocytes

Glia that help form the tight junctions of the BBB.

Ependymal Cells

Produce cerebrospinal fluid (CSF) and circulate it with cilia.

Oligodendrocytes

Glia that produce myelin sheaths in the CNS.

Microglia

Specialized macrophages of the CNS.

Cranial Nerves

There are 12 pairs of cranial nerves.

Optic Nerve (Cranial Nerve II)

Carries signals for vision.

Oculomotor Nerve (Cranial Nerve III)

Carries signals for eyelid movement, lens accommodation, and pupil constriction.

Vagus Nerve (Cranial Nerve X)

Carries signals that decrease breathing and heart rates.

Spinal Cord

Extends from the foramen magnum to about L1-L2 in adults.

Spinal Nerves

There are 31 pairs of spinal nerves.

White Matter

Contains myelinated axons in the spinal cord.

Peripheral Nervous System

Divided into somatic and autonomic divisions.

Neurons

Cells in the CNS that transmit signals.

Myelin Sheaths

Speed up the propagation rate of action potentials.

Saltatory Conduction

Propagation of a nerve impulse along a myelinated neuron.

Perception

Awareness of a sensation.

Sensory Receptors

Pathways that begin at sensory receptors and end in the cerebrum.

Reflex

An automatic, rapid involuntary response to a stimulus.

Axon

Carries a nerve impulse away from the cell body.

Synaptic Vesicles

Store and release neurotransmitters at the axon terminal.

Membrane Potential

The electrical charge difference across a cell membrane.

Action Potentials

All-or-none responses in neurons.

Depolarization

Result of opening voltage-gated Na+ ion channels.

Repolarization

Rapid return of the membrane potential to a negative value.

Undershoot

Hyperpolarization at the end of an action potential.