Autonomic Nervous System Flashcards
Give some examples of sensory information
(4)
Pressure
Temperature
Pain
Hydrogen ion concentration
How is the Nervous System Divided?
The central nervous system and the peripheral nervous system
What is the Peripheral Nervous System
The nervous system outside the brain and spinal cord
What is the peripheral nervous system responsible for?
It transmits information to and from the Central Nervous System
How is the peripheral nervous system divided?
The somatic nervous system and the autonomic nervous system
How is the autonomic nervous system divided?
Into the parasympathetic and sympathetic division
What does the somatic nervous system contral?
Voluntary control e.g. muscle control (skeletal muscle)
What does the autonomic nervous system control?
Involuntary control / smooth muscle
What is the main difference between the nerve cells of the somatic nervous system and the nerve cells of the autonomic nervous system (both sympathetic and parasympathetic)?
In the somatic nervous system the responses are very quick so there is no synapse -> nerve cell reaches out to skeletal muscle -> the release of neurotransmitters at the synapse stimulate the muscle cells
Name a disease that affects the neurons of the somatic nervous system
Motor neuron disease
Give some systems the autonomic nervous system is responsible for controlling
(4)
Blood pressure
Temperature adjustments
Electrolyte balance
Blood gas balance
What tissues does the autonomic nervous system control?
(4)
Smooth muscle
Glands
Cardiac muscle
Adipose tissue
What systems does the autonomic nervous system control?(5)
Cardiovascular System
Respiratory System
Digestive System
Urinary System
Reproductive System
How do the actions of the autonomic nervous system compare to the somatic nervous system?
The actions of the autonomic nervous system are widespread and relatively slow while the somatic are fast and specific
List the five main concentrations the autonomic nervous system controls
Internal H2O concentration
Temperature concentration
Electrolytes
Nutrients
Dissolved gases
What parts of the brain coordinates the autonomic nervous system?
(3)
The hypothalamus
The pons
The medulla oblongata
How do the actions of the sympathetic and parasympathetic divisions compare to each other?
These two divisions of the autonomic nervous system usually have opposite effects e.g. heart rate can go up but gut function can go down
How do the actions of the sympathetic and parasympathetic divisions compare to each other?
These two divisions of the autonomic nervous system usually have opposite effects e.g. heart rate can go up but gut function can go down, the two divisions may also work together but one will usually function at a high level while the other is at a low
Which autonomic division predominates under resting conditions?
Parasympathetic division
Which autonomic division predominates under periods of stress or exertion?
The sympathetic division
Stress = Sympathetic
Are the autonomic divisions ever turned off?
No both the sympathetic and parasympathetic divisions have resting tone -> they are both switched on just with different degrees of activity
What is the parasympathetic response?
“Rest and Repose”
“Rest and Digest”
What happens during the parasympathetic response?
(6)
Building up of body energy stores
Conserves energy
Growth/repair of tissue
Decrease heart function and respiratory function
Increase secretion of salivary and digestive glands
Stimulation of urination and defecation
What is the sympathetic response?
“Fight or Flight”
What happens in a sympathetic response?
(8)
Increased metabolic rate (x2)
Increased cardiac output and blood pressure
Heightened mental alertness
Increased respiratory function and dilation of the airways
Increased blood flow to skeletal muscle
Activation of energy reserves
Activation of sweat glands
Reduction of digestion and urinary function
Describe the nerves of the somatic nervous system
Nerve extends from the spinal cord to the effector skeletal muscle without a synapse
Where are the synapses in the neurons of the autonomic nervous system?
They are found before the nerve reaches the target organ
CNS -> preganglionic neuron -> neurotransmitter released at autonomic ganglion (the stop/synapse) -> post ganglionic neuron -> neurotransmitter released at target tissue
What is the main benefit of the synapses found in the autonomic nervous system?
This allows for divergence (branching) which allows for widespread response
How many pairs of peripheral nerves are there?
12 + 31 = 43 pairs
How many pairs of cranial nerves are there?
12 pairs of cranial nerves make up the peripheral nervous system and connect directly with the brain
How many pairs of spinal nerves are there?
There are 31 pairs of spinal nerves in the peripheral nervous system which connect to the spinal cord
What type of neurons make up the peripheral nerves?
Motor and sensory neurons make up the peripheral nerves and have somatic and motor responses
What is the spinal cord composed of?
An inner core of grey matter
Surrounded by an outer covering of white matter
What is grey matter composed of?
Nerve cell bodies
Glia
Blood vessels
What are glia?
(4)
The connective tissue of the nervous system
Several types of cells
Associated with neurons
Also called neuroglia
What is white matter composed of?
Nerve fascicles
Glia
Blood vessels
What are nerve fascicles?
A bundle of nerve fibres belonging to a nerve in the peripheral nervous system
How is the CNS connected to the ANS?
Nerves (preganglionic nerves) leave the CNS (brain and spinal cord) and move out to tissues where they synapse with postganglionic neurons of the ANS ganglia
What neurotransmitter is released at the synapse between the CNS preganglionic axon and the ANS postganglionic axon?
(3)
The traveling action potential of the preganglionic axon causes acetyl choline to be released by the nerves ending
This gives rise to an action potential on the other side of the synapse at the postsynaptic nerve
The action potential travels along the postganglionic axon which causes the release of another transmitter from the nerve ending at the target tissue
From where do the parasympathetic nerves emerge?
From the brainstem and sacral region
From where do the sympathetic nerves emerge?
They emerge from the thoracic and lumber region of the spinal cord
What does divergence mean?
How one preganglionic nerve can excite many postganglionic nerves by having a synapse on more than one postganglionic nerve
Amplification of a signal
