Untitled Flashcards Set

PNS

All nerves found outside of the brain and spinal cord.

Sensory Division (Afferent)

Sends impulses from the senses to the CNS.

Sympathetic Division

Used in energy situations, preparing the body for stressful or emergency situations.

Parasympathetic Division

Reduces the sympathetic response and provides a resting function.

Motor Division (Efferent)

Sends impulses from the CNS to the muscles and glands.

Nervous System

Master control system that works with the endocrine system.

Sensory Input

Detects stimuli inside and outside the body.

Integration

Processing and interpreting information.

Response

Activation of muscles (motor output) or glands.

Neurons

Conduct impulses around the body, accounting for 10% of major nerve cells.

Neuroglia

'Nerve glue' that supports, insulates, and protects neurons.

Neuron Structure

All neurons have a cell body with processes extending outward.

Cell Body of Neuron

Contains a nucleus, cytoplasm, and organelles.

Dendrites

Bring impulses toward the cell body.

Axon

Sends impulses away from the cell body.

Axon Terminals

End of the axon that releases neurotransmitters to pass the impulse to the next neuron.

Types of Neurons

Classified by the number of processes and their function.

Afferent Neurons

Carry impulses towards the CNS.

Efferent Neurons

Carry impulses away from the CNS.

Interneurons

Connect afferent and efferent neurons.

Myelin

Insulation wrapped around axons to help nerve impulses travel more quickly.

Schwann Cells

Type of neuroglial cell that wraps around the axon to form myelin.

Neurilemma

Outer layer of the Schwann cell.

Myelin Sheath

The wrapping formed by Schwann cells around the axon.

Nodes of Ranvier

Gaps in the myelin sheath, formed by Schwann cells.

Astrocytes

Support neurons and connect them to capillaries.

Microglia

Provide immune response to the CNS.

Ependymal Cells

Secrete and circulate cerebrospinal fluid (CSF).

Oligodendrocytes

Provide myelin insulation to neurons within the CNS.

Satellite Cells

Support and anchor neurons in the PNS.

Neuroglial Functions

Support and protect neuronal functions.

Nerve Impulse

Electrical signal that travels along neurons.

Neurotransmitters

Chemicals released at axon terminals to transmit impulses.

Myelination

Process of wrapping axons with myelin to increase speed of impulse transmission.

Neuroplasticity

The ability of the nervous system to adapt and change.

CNS

Central nervous system, composed of the brain and spinal cord.

PNS Functions

Communication between the CNS and the rest of the body.

Cellular Respiration

Process that provides energy for neuron function.

Action Potential

A rapid rise and fall in voltage across a cellular membrane.

Resting Potential

The state of a neuron when not actively sending signals.

Synapse

The junction between two neurons where communication occurs.

Reflex Arc

A neural pathway that controls a reflex action.

Neural Pathways

Connections between neurons that facilitate communication.

Cerebrospinal Fluid (CSF)

Fluid that cushions and protects the brain and spinal cord.

Neuron Types

Sensory, motor, and interneurons based on their role.

Sodium-Potassium Pump

Helps maintain resting potential in neurons by moving ions.

Ion Channels

Proteins that allow ions to flow across the neuron membrane.

Efferent Pathway

Pathway carrying signals away from the CNS to effectors.

Afferent Pathway

Pathway carrying signals toward the CNS from sensory receptors.

Restorative Function

The role of the parasympathetic division in calming the body.