Nervous System and Neurophysiology

Flashcards for reviewing the key vocabulary terms of nervous system and neurophysiology

Endocrine System

Communication system using slow, long-lasting hormonal instructions affecting broad areas.

Nervous System

Communication system using fast, short-lived nerve signals for precise control of specific areas.

Collect Information (Nervous System)

Gathers sights, sounds, touch, and smells.

Process Information (Nervous System)

Determines what is being detected (e.g., identifying apple pie smell).

Respond to Information (Nervous System)

Reacting to processed information (e.g., understanding spoken words).

Central Nervous System (CNS)

Brain and spinal cord.

Peripheral Nervous System (PNS)

Nerves and ganglia outside the brain and spinal cord.

Sensory (Afferent) Nervous System

Receives sensory input.

Somatic Sensory

Voluntary sensory from the outside world (e.g., seeing, smelling, touching).

Visceral Sensory

Involuntary sensory from the inside world (e.g., blood vessel condition, blood calcium levels, hydration).

Motor (Efferent) Nervous System

Generates a motor response.

Somatic Motor

Conscious muscle movement (e.g., picking something up, exercising).

Autonomic Motor

Involuntary responses (e.g., heart pumping harder, kidney response to dehydration).

Afferent

Sensory, carries information TO the brain.

Efferent

Motor, carries instructions AWAY from the brain.

Somatic Afferent

Conscious sensations like touch.

Visceral Afferent

Sensations from within the body.

Somatic Motor

Conscious motor actions.

Autonomic Motor

Involuntary bodily functions.

Nerve

A large cord composed of smaller cords.

Nerve Fiber (Axon)

The smallest component of a nerve, wrapped in endoneurium.

Endoneurium

Innermost layer of wrapping around the axon.

Fascicle

A bundle of nerve fibers wrapped in perineurium.

Perineurium

Middle layer, covering a bundle of nerve fibers (fascicle).

Epineurium

Outermost layer, a tight wrapping around multiple fascicles, forming the nerve.

Neuron

The cell that makes up the nervous system, designed to collect and transmit information.

Dendrites

Receive information from neighboring neurons, organs, etc.

Cell Body (Soma)

Processes information received by dendrites; determines if the signal is significant enough to pass on.

Axon

Long structure that transmits significant information to axon terminals.

Axon Terminals

Pass information to neighboring neurons.

ATP

Passing information requires this.

Mitochondria

Nerve cells contain many of these to produce ATP.

Oxygen

Required for ATP production; nerves have a rich blood supply to deliver oxygen and glucose.

Ganglion

A cluster of neuron cell bodies (somas) grouped together.

Spinal Nerves

31 pairs of nerves coming directly from the spinal cord.

Cranial Nerves

12 pairs of nerves coming directly from the brain that controls the face and head.

Sensory Nerves

Carry sensory information (afferent).

Motor Nerves

Carry motor instructions (efferent).

Mixed Nerves

Contain both sensory and motor fibers (two-way streets).

Excitability

Ability to get excited (respond to stimuli).

Conductivity

Ability to carry a signal (electrical impulse/information) quickly.

Secretion

Ability to secrete neurotransmitters to communicate with neighbors.

Longevity

Neurons can live for a lifetime but cannot replicate (no mitosis).

Axon Hillock

The location where information transmission begins.

Multipolar Neuron

Many dendrites, one axon (most common).

Bipolar Neuron

One dendrite, one axon.

Pseudo-Unipolar Neuron

One long, connected structure with a pit stop at the soma.

Interneuron

A bridge between sensory and motor information, commonly seen in reflexes.

Synapse

The space between two neurons where communication occurs.

Presynaptic Neuron

The neuron before the synapse.

Postsynaptic Neuron

The neuron after the synapse.

Chemical Synapse

Communication via neurotransmitters.

Electrical Synapse

Communicating via electrical signals (rare).