The Nervous System:

Neuromuscular Junction

The site where a nerve cell communicates with a muscle fiber to initiate contraction.

Peripheral Nervous System (PNS)

The part of the nervous system made up of cranial nerves, spinal nerves, ganglia, and enteric plexuses, responsible for relay between the CNS and the rest of the body.

Afferent Division

The division of the PNS that brings sensory information from receptors to the CNS.

Efferent Division

The division of the PNS that carries motor commands from the CNS to effectors such as muscles and glands.

Somatic Nervous System

Part of the PNS that controls voluntary muscle movements.

Autonomic Nervous System

A component of the PNS that regulates involuntary physiological processes.

Central Nervous System (CNS)

The part of the nervous system consisting of the brain and spinal cord, responsible for processing information.

Action Potential

Another name for an impulse, an electrical signal generated in neurons.

Node of Ranvier

Gaps in the myelin sheath that allow electrical impulses to travel quickly along an axon.

Nerve Impulse

An electrical signal that travels along a nerve fiber in response to a stimulus.

Myelin Sheath

An insulating layer around nerve fibers, composed of lipids and proteins, that speeds up signal transmission.

Neurotransmitter

A chemical messenger that carries signals between nerve cells.

Adrenergic Synapse

A synapse that releases norepinephrine (NE) as a neurotransmitter.

Somatic Nervous System Functions

Controls voluntary movements by sending signals from the brain to skeletal muscles.

Optic Nerve (Cranial Nerve 2)

Carries visual information from the eyes to the brain.

Trigeminal Nerve (Cranial Nerve 5)

Mixed nerve responsible for sensation in the face and motor functions such as biting and chewing.

Abducens Nerve (Cranial Nerve 6)

Innervates the lateral rectus muscle, controlling eye movement.

Facial Nerve (Cranial Nerve 7)

Controls muscles of the face and scalp; receives taste information from the tongue.

Vestibulocochlear Nerve (Cranial Nerve 8)

Monitors balance and hearing.

Accessory Nerve (Cranial Nerve 11)

Innervates voluntary swallowing muscles and muscles associated with the pectoral girdle.

Hypoglossal Nerve (Cranial Nerve 12)

Provides motor control over tongue movements.

Parasympathetic Nervous System

Responsible for stimulating activities of smooth muscles, cardiac muscles, and glands.

Sympathetic Nervous System

Prepares the body for 'fight or flight' responses; affects the same organs as the parasympathetic system.

Neuroglia

Supportive cells in the nervous system that maintain homeostasis and provide protection.

Sensory Cells

Cells that detect environmental stimuli through specialized receptors.

Function of the Nervous System

Acts as the body’s communication network, coordinating functions such as movement, sensation, and cognition.

Dendrites

Branch-like structures of neurons that receive information from other neurons.

Receptor Cells

Protein molecules that bind substances like hormones and drugs, initiating cellular responses.

Cranial Nerves

A set of twelve nerves that originate in the brain, responsible for various functions such as sensory and motor control.

Cranial Nerves Functions

Each cranial nerve is associated with specific sensory and motor functions within the body.

Enteric Plexuses

A network of neurons located in the walls of the gastrointestinal tract.

Ganglia

Collections of nerve cell bodies in the peripheral nervous system.

Afferent Neurons

Neurons that carry sensory information from receptors to the CNS.

Efferent Neurons

Neurons that carry motor commands away from the CNS to muscles and glands.

Chemical Messenger

Another term for neurotransmitters that transmit signals between neurons.

Adrenal Glands

Glands that produce hormones for stress response, regulated by the sympathetic nervous system.

Memory

The processing and retention of information by the central nervous system.

Learning

The acquisition of knowledge or skills through experience, frequently involving changes in the nervous system.

Intelligence

The ability to acquire and apply knowledge and skills, a function primarily attributed to the brain.

Soma

The cell body of a neuron, containing the nucleus and organelles.

Impulse Transmission

The process of propagating an electrical signal along a nerve fiber.

Neural Tissue

Tissue composed of neurons and neuroglia, responsible for transmitting signals throughout the body.