Coordination + Control: Nervous System Flashcards
Nervous System Definition
a control system comprising of neurones connected in networks
To control essential sensory, motor and complex functions of an organism
What are the 2 components that the Central Nervous System tissue is made up of?
Neurones
Glial cells
What is a neurone?
- Electrically active cells capable of transmitting information.
- Link to other neurones or muscle cells through SYNAPSES by releasing NEUROTRANSMITTERS
What are glial cells?
Supportive cells:
- Provide mechanical support
- Maintain an optimal physiochemical
environment
Some types produce myelin - a lipid material - white in appearance –> helps to insulate axons of neurons
What makes up the CNS
made up of brain (within skull) and spinal cord (within vertebral column)
2 Way information flow:
Stimulus -> Nervous system -> Response
Input -> Nervous System -> Output
Term for information traveling TOWARDS the CNS
= sensory (Afferent)
Term for information traveling AWAY from the CNS
= motor (Efferent)
Components of the peripheral nervous system
Cranial nerves
Spinal nerves
Associated ganglia
Sensory Division:
General Somatic Afferent (GSA)
General: Touch, pain, vibration, temperature, pressure
Special: hearing, vision, balance
Sensory Division:
General Visceral Afferent (GSA)
General: stretch, pain, temperature, chemical changes and visceral irritation, nausea and hunger
Special: smell and taste
Motor division:
General Somatic Efferent (GSE)
Motor innervation of all skeletal muscles
Motor division:
General Visceral Efferent (GVE)
Motor innervation of smooth and cardiac muscles, glands
Autonomic nervous system definition
A nervous control system that functions below the level of consciousness and controls visceral functions
- Unconscious control
- ANS present in both CNS and PNS
- has two divisions the Sympathetic (fight or flight) and Parasympathetic nervous system
What does the autonomic nervous system control
Controls involuntary structures
e.g. heart, lungs, gastrointestinal tract, smooth muscle, glands, pupils
What is grey matter?
mainly cell bodies
Neurone cell bodies, dendrites and unmyelinated axons
What is white matter?
mainly myelinated axons
Where is grey matter found in the brain?
Found on the surface and in deep ‘nuclei’ (clumps of cell bodies)
White matter forms tracts
Where is grey matter found in the spinal cord?
forms an internal column (horns) surrounded by external white matter
Where is grey matter found in the PNS?
neuronal cell bodies in ganglia lying outside spinal cord
Where is white matter found?
Funiculi/ Columns
Fasciculi / tracts
What is Funiculi/ Columns
large bundles of white matter in the spinal cord surrounding horns
Fasciculi / tracts
White matter in brain or spinal cord
What is Cerebrospinal fluid (CSF)?
- like plasma but without protein
- fills cerebral ventricles of brain, central canal of spinal cord and flows over surface of tissue
- fluid ends up being absorbed into venous blood via meninges
Functions of cerebrospinal fluid:
Cushion, homeostasis, chemical buffer
Forebrain
= large area of cortex - many complex functions
What is the Midbrain
- tracts ascending and descending
Hindbrain
- continuous with spinal cord –> contains medulla, cerebellum, pons
3 Components of the brain stem:
Midbrain, pons, medulla
In the brain what are:
Gyri (gyrus)
=Hills
In the brain what are:
Sulci (sulcus)
= grooves
In the brain what are:
Fissures
= a deep groove or cleft
What are the 4 anatomical lobes in human brain? ( in cerebral hemispheres)
Frontal lobe –> Motor area
Temporal lobe –> Auditory cortex
Occipital lobe –> Visual cortex
Parietal lobe –> Sensory area
What is the structure and function of the corpus callosum ( forebrain white matter) ?
Structure = Wide, flat bundle of myelinated axons that cross between cerebral hemispheres
Function = inter - hemispheric communication
Largest white matter structure of the brain
Cerebral Cortex
cerebral hemispheres covered by sheet of cerebral cortex (grey matter)
Makes up 80% of brain
Right and left sides of cortex are connected by thick band of nerve fibres called corpus callosum –> (white body)
