Nervous system

Central Nervous System

Comprises the brain and spinal cord, responsible for processing and transmitting information.

Peripheral Nervous System

Divided into cranial and spinal nerves, connecting the CNS to the rest of the body.

Cranial Nerves

Nerves that emerge directly from the brain, conveying sensory information and messages to muscles and glands.

Spinal Nerves

Emerge at regular intervals from the spinal cord, transmitting sensory information from the body to the brain.

Nerves

Collections of nerve fibers transmitting information to and from the CNS, classified into Class A, B, and C based on functions.

Class A Nerves

Largest and thickest nerves responsible for muscle and tendon movements, usually myelinated for rapid transmission.

Class B Nerves

Cover involuntary impulses like digestion and breathing, myelinated but thinner than Class A nerves.

Class C Nerves

Unmyelinated nerves responsible for pain and temperature sensations, slower but reaching all body parts equally.

Brain Stem

Primitive brain region controlling physiological functions and automatic behaviors like breathing and heartbeat.

Cerebellum

Coordinates movements, balance, posture, and voluntary movements, involved in motor learning and cognitive functions.

Blood-Brain Barrier

Protects the brain from harmful substances by restricting their passage from the blood into the brain, formed by tight capillaries with tight junctions.