Autonomic system Flashcards
What is the nervous system for skeletal muscles? and what is the function of it?
The Somatic NS allows point-to-point, precise and fast control of skeletal muscles
What is the nervous system for visceral muscles and tissues? and what is the function of it?
Autonomic NS mediates relatively rapid responses, using direct nerve control of peripheral structures.
Where do the responses of ANS target?
The responses can be specific to a target tissue but widespread across the whole body
What can the actions of the ANS be supplemented by? What can it do?
They can be supplemented by the action of hormones, which produce slow and diffuse effects and multiple tissues and organs might be affected.
What is the nervous system for hormonal tissues and glands? and what is the function of it?
Endocrine system releases hormones into the blood. Still for tissue-specific or diffuse, integrative and long term control of tissues, glands and organs
What are the features of the ANS?
- A persuasive neural network that maintains homeostasis within the body and regulates the responses of the body to its environment.
- Effects can occur routinely and automatically without volitional (conscious) control
- Effects are initiated in anticipation of a perturbation
- Linked to and coordinated with the Somatic NS
What are the advantages of ANS controlling the autonomic functions?
- Produce relatively fast response of perturbation
- Coordination across wide regions across the body
- Has the capacity to be flexible in types of responses that it produces
- Acts on structures with intrinsic activity.
The ANS consists of a loop. What does it have to do?
- Receive feedback info from the internal sensory systems
- Be integrated with the somatic and endocrine control systems.
- Receive higher oder inputs
What are the 3 components in the ANS loop?
- Motor efferent arm
- High level integrative control
- Sensory afferent feedback
What are the two divisions in the motor arm of the ANS loop?
- Sympathetic
- Parasympathetic
Where is the preganglionic neuron located in the sympathetic division of the motor arm?
Thoracic and Lumbar regions of the spinal cord. (T1 - L3)
The ANS consists of a neural loop. What does it do?
- Receive feedback info from internal sensory systems
- Be integrated with somatic and endocrine systems
- Receive higher order inputs
What are the 3 components in a neural loop (ANS)?
- A motor efferent arm
- High-level integrative control/brain stem controllers
- Sensory afferent feedback
Where is the motor efferent arm of the neural loop located? Where does it run to?
The neurons originate in the spinal cord and brain stem. They run to a ganglion to contact a set of motor neurons which are the final arm for the motor control tissues
What is the function of the brain stem controllers?
Get controller or modulatory input from higher brain centres
Where does the sensory feedback from target tissues travel back to?
Back to the brain stem, spinal cord and thalamus
What part of the brain receives sympathetic input?
Adrenal medulla
What do parasympathetic nerves innervate?
Salivary and GI glands, genital erectile tissues and skin blood vessels. They both work synergistically to achieve an end output
What is the function of Enteric nervous system?
Confine to and control the functions of Gastrointestinal tract
Where do preganglionic neurons receive their inputs? Where is it located?
From the midbrain and brainstem, the higher regions of the brain. Parasympathetic preganglionic neurons are located in the brainstem or in the Sacral (S1-S3)
What is the function of the postganglionic neuron?
Their axon runs from the ganglion to the target tissue.
What is the process for CNS to reach the target tissue?
CNS ~> Preganglionic neuron ~> Postganglionic neuron ~> Target tissue
What is the function of iontropic receptors?
Produce rapid effects in the target cell after they bind the transmitter
Where does the hyptothalamus intergrate inputs from?
-Brain stem nucleus of solitary tract
-Reticular formation
-Retina
-Circumventricular nuclei
-REceptors within the hypothalamus itself
