Nervous System I: Basic Structure and Function

Practice flashcards covering vocabulary terms and definitions related to the structure and function of the nervous system.

Nervous System

The master regulatory system that sends and receives information, maintains homeostasis, and acts as a center for thought, learning, and memory.

Neurons

Nerve cells that respond quickly to changes and conduct electrical impulses via neurotransmitters.

Neuroglia

Supportive cells in the nervous system that protect, support, insulate, and nourish neurons without conducting electrical impulses.

Central Nervous System (CNS)

Comprises the brain and spinal cord.

Peripheral Nervous System (PNS)

Connects the CNS to other body parts, consisting of cranial nerves and spinal nerves.

Afferent Division

Sensory division of the PNS that transmits sensory information to the CNS.

Efferent Division

Motor division of the PNS that transmits commands from the CNS to effectors like muscles and glands.

Somatic Nervous System

Part of the PNS that transmits voluntary commands to skeletal muscles.

Autonomic Nervous System

Part of the PNS that transmits involuntary commands to smooth muscles, cardiac muscles, and glands.

Myelin Sheath

A insulating covering around some axons, composed of Schwann cell membranes and myelin, which acts as an electrical insulator.

Action Potential

A sequence of electrical events involving changes in membrane potential used for communication between cells.

Threshold Potential

The critical level to which a membrane potential must be depolarized in order to initiate an action potential.

Neurotransmitters

Chemical messengers that transmit signals across synapses from one neuron to another.

Excitatory Postsynaptic Potential (EPSP)

A membrane change that depolarizes the postsynaptic neuron, making an action potential more likely.

Inhibitory Postsynaptic Potential (IPSP)

A membrane change that hyperpolarizes the postsynaptic neuron, making an action potential less likely.

Convergence

The process in which multiple neurons send input to a single neuron.

Divergence

The process in which a single neuron sends impulses to multiple neurons.