BIO 210 Test 4 Study Guide Chapter 12-14

A comprehensive set of vocabulary flashcards based on key topics from the BIO 210 Test 4 Study Guide covering the nervous system, brain functions, sensory receptors, and reflex arcs.

Nervous system functions

Communication, control, integration.

CNS

Central Nervous System, includes the brain and spinal cord.

PNS

Peripheral Nervous System, consists of nerves.

Somatic nervous system

Voluntary control of body movements.

Autonomic nervous system

Involuntary control of body functions.

Neuron components

Includes the cell body, dendrites, and axon.

Cell body

Largest part of neuron, contains nucleus and organelles.

Dendrite

Process of neuron that carries impulses toward cell body.

Axon

Process of neuron that carries impulses away from cell body.

Unipolar neuron

One split axon with one branched dendrite, primarily sensory.

Bipolar neuron

One axon and one branched dendrite, least common; found in the eye and inner ear.

Multipolar neuron

One axon and multiple dendrites; most common type of neuron.

Afferent neurons

Neurons that carry signals towards the CNS.

Efferent neurons

Neurons that carry signals away from the CNS to effectors.

Interneuron

Neuron that connects afferent and efferent neurons.

Impulse conduction order (multipolar)

Dendrites -> cell body -> axon.

Astrocytes

Glial cells that protect the brain.

Microglia

Small, mostly stationary glial cells that enlarge and phagocytize during infection.

Ependymal cells

Epithelial cells that line fluid-filled spaces in the central nervous system.

Oligodendrocytes

Glial cells that produce myelin for axons in the CNS.

Schwann cells

Glial cells in the PNS that produce myelin around axons.

Resting membrane potential

State where a neuron is not conducting an impulse.

Polarization

Resting state of the neuron with positive outer surface and negative inner surface.

Na+/K+ pump

Pump that uses ATP to move sodium out of and potassium into the cell.

Threshold

The level that must be reached for an action potential to occur.

Depolarization

Phase where sodium channels open and sodium enters the cell.

Repolarization

Phase where potassium channels open, returning the membrane to resting potential.

Absolute refractory period

Period during which another action potential cannot be initiated.

Relative refractory period

Period where another action potential can occur only with a stronger stimulus.

Synaptic transmission

Process through which neurotransmitters are released across synaptic clefts.

Cerebrum

Largest part of the brain, responsible for various lobe functions.

Cerebellum

Part of the brain involved in coordination and balance.

Thalamus

Major relay station for sensory impulses.

Hypothalamus

Regulates bodily functions such as temperature, hunger, and emotions.

Pineal body

Secretes melatonin; involved in the regulation of circadian rhythms.

Broca's area

Area of the brain responsible for speech production.

Wernicke's area

Area of the brain responsible for language comprehension.

Spinal cord gray matter

Central 'butterfly' structure composed mostly of cell bodies.

Spinal cord white matter

Surrounds gray matter, composed mainly of axons.

Ascending tracts

Sensory pathways in the spinal cord that carry information from peripheral receptors up to the brain.

Descending tracts

Motor pathways in the spinal cord that transmit signals from the brain down to motor neurons controlling muscles and glands.

Endoneurium

Connective tissue wrapping around individual nerve fibers.

Perineurium

Connective tissue wrapping around groups of nerve fibers (fascicles).

Epineurium

Connective tissue wrapping around the entire nerve.

Cranial nerves

Twelve pairs of nerves responsible for various sensory and motor functions.

Cranial Nerve I: Olfactory

Sensory, responsible for the sense of smell.

Cranial Nerve II: Optic

Sensory, responsible for vision.

Cranial Nerve III: Oculomotor

Motor, controls most eye movements, pupil constriction, and eyelid opening.

Cranial Nerve IV: Trochlear

Motor, controls superior oblique eye muscle movement.

Cranial Nerve V: Trigeminal

Both (Sensory and Motor), provides sensation to the face and controls muscles of mastication (chewing).

Cranial Nerve VI: Abducens

Motor, controls lateral rectus eye muscle movement.

Cranial Nerve VII: Facial

Both (Sensory and Motor), controls facial expressions, taste sensation (anterior two-thirds of tongue), and salivation/lacrimation.

Cranial Nerve VIII: Vestibulocochlear

Sensory, responsible for hearing and balance.

Cranial Nerve IX: Glossopharyngeal

Both (Sensory and Motor), responsible for taste (posterior one-third of tongue), salivation, and swallowing.

Cranial Nerve X: Vagus

Both (Sensory and Motor), controls involuntary functions of viscera (heart rate, digestion), swallowing, and voice production.

Cranial Nerve XI: Accessory

Motor, controls neck and shoulder muscle movement (sternocleidomastoid and trapezius).

Cranial Nerve XII: Hypoglossal

Motor, controls tongue movements.