The Central Nervous System Flashcards
What does vestigial mean?
The retention of genetically determined attributes that have lost some of their function.
E.g. eyebrow flashing - completely unconscious & indicates a desire for social contact.
What are the subdivisions of the nervous system?
Central nervous system
Peripheral nervous system
What are the subdivisions of the central nervous system?
Brain
Spinal cord
What are the subdivisions of the peripheral nervous system?
Autonomic NS
Somatic NS
What are the subdivisions of the autonomic nervous system?
Sympathetic NS
Parasympathetic NS
What are the subdivisions of the somatic NS?
Sensory neurones
Motor neurones
What are dendrites?
Where the neurone receives electrochemical input from other neurones.
Critical in integrating synaptic inputs and determining action potentials produced by the brain.
What is the role of the axon?
It carries input away from the neurone and transmits information to other neurones
What is the myelin sheath?
Insulates the axon.
Increases the rate at which electrochemical signals pass down the axon.
Why are the nodes of ranvier important?
They allow the electrical impulse to move quickly down the axon.
Why are synapses useful?
Allows a neurone to communicate its electrochemical signal to a neurone via the dendrites.
What is the role of neuroglia cells?
Provides and controls nutrients and chemicals to neurones.
Insulates neurones from each other avoiding electrochemical messages being disrupted.
Why are astrocytes important?
Responsible for forming the blood-brain barrier and providing neurones with nutrients.
Why are oligodendrocytes important?
Cells that form the myelin sheath which are found exclusively in the CNS.
What are unipolar neurones?
Only one neurite extends from the soma.
