Nervous System ll

Flashcards covering the key vocabulary and concepts of the nervous system.

Neuron

A specialized body cell that is part of the nervous system.

Central Nervous System (CNS)

The brain and spinal cord.

Peripheral Nervous System (PNS)

All nervous system components outside the brain and spinal cord, such as nerves throughout the body.

Somatic Nervous System (SNS)

The part of the PNS that controls voluntary skeletal muscle actions and reflexes.

Autonomic Nervous System (ANS)

The part of the PNS that manages involuntary functions like digestion, heart rate, and endocrine activity.

Sympathetic System

The division of the ANS responsible for the "fight or flight" response.

Parasympathetic System

The division of the ANS associated with "rest and digest."

Neurons

Nervous tissue cells that have a cell body, dendrites, and an axon.

Glial Cells

Nervous tissue cells essential for support, chemical balance, forming the blood-brain barrier, producing cerebrospinal fluid, creating myelin sheaths for insulation, and immune defense.

Resting Membrane Potential

The electrical difference between the inside and outside of a cell (typically negative inside).

Action Potential

Electrical signal neurons use to communicate. It is an all-or-none response.

Depolarization

The process where sodium floods into the axon, causing the neuron to become more positive.

Repolarization

The process where potassium floods out of the axon, causing the neuron to return to its resting membrane potential.

Hyperpolarization

The process where too much potassium floods out of the axon causing the membrane potential to drop below resting membrane potential.

Refractory Period

The period of time during which an excitable cell cannot generate another action potential.

Sodium-Potassium Pump

A cellular pump that uses ATP to move sodium ions out of the cell and potassium ions into the cell, maintaining resting membrane potential.

Local Anaesthetics

Drugs that block pain and other somatic sensations by blocking the opening of voltage gated Na channels.