7- The autonomic nervous system Flashcards
What is anxiety?
A feeling of worry, nervousness, or unease, typically about an imminent event or something with an uncertain outcome.
What are some of the physical symptoms of anxiety?
Racing heart
Heavy breathing
Sweating
Dry mouth
What are the 2 divisions of the nervous system?
- Central nervous system (brain and spinal
2. Peripheral nervous system
What is the peripheral nervous system split into?
- The somatic nervous system
2. The autonomic nervous system
What does the somatic nervous system control?
Controls external actions of skin and muscles
What does the autonomic nervous system control?
Controls internal actions of organs and glands
What can the autonomic nervous system be split into?
- Sympathetic
2. Parasympathetic
What are somatic motors?
Efferent fibres travelling TO the striated (skeletal) muscle
What are somatic sensory pathway?
afferent fibres COMING from receptors
How many spinal nerve do we have?
31
What type of reaction results from the autonomic nervous system?
A largely involuntary reaction
What does the autonomic nervous system monitor?
Monitors conditions in the internal environment to maintain homeostasis
What is homeostasis?
Homeostasis is a dynamic balance between the sympathetic and parasympathetic nervous systems
What is that parasympathetic nerve system describes as?
‘Rest and digest’
What is that sympathetic nerve system describes as?
‘Fight or flight’
What are the 2 divisions of the autonomic nervous system?
Sympathetic and Parasympathetic
From which branch of the ANS do most visceral organs receive information from?
Most visceral organs receive both sympathetic and parasympathetic
What type of effect to the parasympathetic and sympathetic nervous systems have on each other?
They Exert an antagonistic effects
What does the parasympathetic nervous system sustain?
Sustains normal bodily functions
Conserves and restores energy
What does the parasympathetic nervous system prepare us for?
Rest and Digest
What do visceral organs send?
sensory afferent fibres to the CNS
What do visceral organs receive?
Motor Efferent fibres from CNS
What are autonomic (visceral) motor fibres and where do they go?
They are efferent fibres that travel to smooth muscles, cardiac muscle or glands
What are autonomic (visceral) sensory fibres and where do they come form?
They are afferent fibres from sensory receptors in an internal organ
Where is the lateral grey horn present?
Between the levels of:
T1-L2
S2-S4
From where do visceral motor neurones exit the spinal cord?
Via the lateral grey horn
How many neurones makes up the efferent system of the autonomic nervous system?
2 neurone chain
Name the 2 neurones involved in transmitting efferent signals in the ANS
- Preganglionic neurone
2. Postganglionic neurone
Where is the preganglionic neurone that transmits efferent signals in the ANS found?
Somewhere in the CNS (Either the brainstem or spinal cord)
Where is the postganglionic neurone that transmits efferent signals in the ANS found?
Somewhere in the PNS
Why are the Preganglionic neurone and Postganglionic neurone given these name?
Because they synapse at the autonomic ganglion
Where is the autonomic ganglion found?
In the PNS
Where is sympathetic outflow coming from ?
Comes from the levels T1-L2 (Thoracolumbar outflow)
Where is parasympathetic outflow coming from ?
Brainstem: cranial nerves III,VII, IX, X
Spinal cord: S2-S4
Describe the structure if the sympathetic nervous system
Organised ganglia in sympathetic chain, and prevertebral ganglia
Where are the ganglia located In the parasympathetic nervous system?
Near the effector organ