The Nervous System Quiz

Sensory Input

Receives stimuli via millions of sensory receptors throughout the body.

Integration

Processes input stimuli and decides what should be done.

Motor Output

Activates effector organs to cause a response.

Nervous Tissue

Composed of neurons and neuroglia.

Neurons (nerve cells)

Excitable cells that respond to stimuli by conducting impulses to transmit signals.

Neuroglia (glial cells)

Supportive cells that provide nutrition, insulation, and help with signal transmission.

Soma (cell body)

Life support of the neuron, containing the nucleus and organelles.

Processes

Extensions from the cell body.

Dendrites

Main receptor of signals; input region.

Axon

Generates and transmits nerve impulses; conducting region (also called a nerve fiber).

Axon Terminals

End of the axon that releases neurotransmitters at a synapse; secretory region.

Myelin Sheath

Covers long axons to protect and electrically insulate, increasing impulse speed.

Nodes of Ranvier

Unmyelinated gaps that help increase nerve signal velocity.

Nerves

Bundles of axons extending from the brain and spinal cord to the rest of the body.

Ganglion

Collection of nerve cell bodies located outside the brain or spinal cord.

Multipolar Neurons

More than 3 processes (1 axon, 2+ dendrites); 99% of neurons.

Bipolar Neurons

2 processes (1 axon, 1 dendrite); rare, found in special sense organs.

Unipolar Neurons

1 process dividing from the cell body like a T; found in PNS ganglia.

Sensory (afferent) neurons

Transmit info from sensory receptors to CNS; mostly unipolar.

Motor (efferent) neurons

Transport info from CNS to body; mostly multipolar.

Interneurons (association neurons)

Housed in CNS; transmit info between sensory and motor neurons; mostly multipolar.

Central Nervous System (CNS)

Brain and spinal cord; integration and control center.

Peripheral Nervous System (PNS)

Spinal and cranial nerves; communication system between CNS and body.

CNS Protection

The brain is protected by the skull, meninges, and cerebrospinal fluid.

Ventricles

Hollow fluid-filled cavities in the brain containing the choroid plexus, which produces cerebrospinal fluid.

Cerebrum

Largest part of the brain; left and right hemispheres, divided into 4 lobes; functions in learning, speech, emotion, reasoning, vision, hearing, and fine movements.

Cerebellum

Under the cerebrum; maintains posture and balance; coordinates timing and patterns for smooth, agile, subconscious movements.

Brainstem

Base of the cerebrum, anterior to the cerebellum; includes medulla oblongata, midbrain, and pons; relays info between the brain and spinal cord.

Frontal Lobe

Handles decision-making, planning, problem-solving, and voluntary muscle movement.

Parietal Lobe

Processes touch, temperature, pain, and helps with spatial awareness.

Occipital Lobe

Responsible for processing visual information.

Temporal Lobe

Manages hearing, memory, and understanding language.

Thalamus

Acts as a relay station, directing sensory information to the appropriate areas of the brain.

Hypothalamus

Regulates body temperature, hunger, thirst, sleep, and hormone release.

Pituitary Gland

Produces and releases hormones that control growth, metabolism, and other endocrine glands.

Pineal Gland

Produces melatonin, which regulates sleep-wake cycles.

Spinal Cord

Transmits signals between the brain and the body and coordinates reflexes.

Dendrites

cell body

axon

axon terminal

myelin sheath

sulci

gyri