31/03 Lecture 16 - Neuroanatomy I

CNS

This is a division of the nervous system consisting of the brain and spinal cord

PNS

This is a division of the nervous system consisting of nervous tissue outside of the brain and spinal cord

Somatic nervous system

This is a division of the efferent PNS responsible for voluntary muscle activity

Autonomous nervous system

This is a division of the efferent PNS responsible for regulating homeostatic activity

Parasympathetic nervous system

This is a division of the ANS responsible for ‘rest and digest’ activity

Sympathetic nervous system

This is a division of the ANS responsible for ‘fight or flight’ activity

Axoplasmic transport

This is the mechanism of transport for intracellular structures across the neuron

Retrograde flow

This describes the movement of debris or unusual chemicals from the axon to the cell body

Dendrite

This is a highly branched structure that extends from the cell body and receives electrochemical signals from other neurons

Axon

This is a long extension of the cell body composed of the axon hillock, initial segment, axolemma, and axoplasm

Cell body

This is the main segment of the neuron composed of the perikaryon, and support by neurofilaments and neurofibrils

Telodendria

This describes fine extensions at the distal end of the neuron

Synaptic terminals

This describes points where the neuron releases neurotransmitters into the synaptic cleft

Collateral branches

This describes branches extending from the axon of a neuron that allow it to communicate with multiple cells simultaneously

Interoceptor

This receptor monitors the digestive, respiratory, cardiovascular, urinary, and reproductive function

Proprioceptor

This receptor monitors the position and movements of skeletal muscles

Exteroceptor

This receptor monitors the external environment through sensory perception

Efferent fibres

This describes axons that carry information from the CNS to the PNS

Afferent fibres

This describes axons that carry information from the PNS to the CNS

Somatic sensory neuron

This neuron receives and processes information from proprioceptors and exteroceptors

Visceral sensory neuron

This neuron receives and processes information from interoceptors

Ependymal cells

This is a type of cell responsible for forming the ependyma that lines the central canal and ventricles, as well as producing and maintaining CSF

Microglia

This is a type of cell responsible for cleaning and removing cellular debris, waste, and attacking pathogens

Astrocytes

This is a type of cell responsible for supplying nutrients to neurons, maintaining the blood-brain barrier, and responding to CNS injury

Oligodendrocytes

This is a type of cell responsible for creating the myelin sheath and supporting nerve fibres

Ependymocytes

This is a type of ependymal cell responsible for circulating CSF around the brain and spinal cord with motile cilia

Tanycytes

This is a type of ependymal cell responsible for transporting substances between the CSF and brain

Myelinated

This describes that state of an axon being surrounded by a myelin sheath

Internodes

This describes stretches of axon surrounded by a myelin sheath

Nodes of Ranvier

This describes small gaps of unmyelinated axon between internodes

White matter

This describes regions of nervous tissue dominated by myelinated axons

Grey matter

This describes regions of nervous tissue dominated by unmyelinated axons

Neurilemma

This is the outer surface of a Schwann cell

Schwann cell

This is a type of glial cell that covers peripheral axons with a myelin sheath and repairs axons after injury

Wallerian degeneration

This is the repair process of PNS neurons by Schwann cells that fails to restore full function

Tract

This is a bundle of axons

Nerve

This is a bundle of functional axons in the PNS

Synaptic cleft

This is the gap in between the terminal of one neuron and the dendrites of another neuron