Organisation and Functional Anatomy of the Nervous System

Central Nervous System (CNS)

Includes brain and spinal cord; command center.

Peripheral Nervous System (PNS)

Nerves extending from CNS to body parts.

Sensory Neurons

Afferent neurons delivering impulses to CNS.

Motor Neurons

Efferent neurons carrying impulses from CNS.

Neuroglial Cells

Supportive cells providing insulation and nutrients.

Myelin Sheath

Insulating layer increasing signal transmission speed.

Node of Ranvier

Gaps in myelin allowing action potential jumps.

Dendrites

Extensions increasing surface area for signals.

Axon

Transmits information from neuron to neuron.

Synapse

Gap between neurons for chemical communication.

Neurotransmitters

Chemicals transmitting signals across synapses.

Resting Potential

Neuron's inside negative at -70 mV.

Reflex Arc

Neural pathway producing involuntary movements.

Somatic Nervous System

Controls voluntary muscle movements and sensory input.

Autonomic Nervous System

Regulates involuntary physiological processes.

Sympathetic Nervous System

Prepares body for stress; fight or flight.

Parasympathetic Nervous System

Restores body to calm state; rest and digest.

Enteric Nervous System (ENS)

Regulates digestive processes independently of CNS.

Cerebrum

Largest brain part; responsible for higher functions.

Cerebellum

Coordinates movement and balance.

Medulla Oblongata

Controls autonomic functions like breathing.

Afferent Pathway

Carries sensory information to the CNS.

Efferent Pathway

Carries motor information from the CNS.

Multipolar Neurons

Neurons with many processes; found in CNS.

Bipolar Neurons

Neurons with two processes; found in sensory organs.

Unipolar Neurons

Neurons with one process; found outside CNS.

Interneurons

Connect sensory and motor neurons in CNS.

Graded Potentials

Changes in membrane potential; signal transmission.

Excitatory Neurotransmitters

Cause depolarization in receiving neurons.

Inhibitory Neurotransmitters

Cause hyperpolarization in receiving neurons.

Somatosensory System

Processes touch, pain, temperature, and position.

Cerebral Cortex

Outer layer of cerebrum; involved in perception.

Filum Terminale

Extension of conus medullaris anchoring spinal cord.

Cervical Enlargement

Thickening of spinal cord for upper limbs.

Lumbar Enlargement

Thickening of spinal cord for lower limbs.