Autonomic Nervous System Flashcards
Which division of the PNS corresponds to the autonomic NS?
Visceral motor system
What does the autonomic nervous system control?
Glands, cardiac muscle, smooth muscle
What are the two branches of the autonomic nervous system (ANS), and what physiological responses does each of them regulate?
- Parasympathetic NS: Rest & digest response
- Sympathetic NS: Flight-or-fight stress response
What are the effects of sympathetic activation?
Pupils dilate, salvation is inhibited, bronchi relax, heart rate increases, digestive activity is inhibited, increased release of glucose, increased EPI & NE secretion, inhibition of urination.
What constitutes the primary distinction in the definitions of visceral and somatic reflexes?
Visceral reflexes are initiated by stimulus in the viscera.
What are the 5 components of a visceral reflex arc?
- Receptors (in viscera)
- Afferent (sensory) neuron
- Interneuron
- Efferent (motor) neuron
- Effector (viscera)
What types of stimuli are detected by receptors in the viscera?
Stretch, tissue damage, blood chemistry, body temperature, and other internal stimuli
What is an autonomic ganglion? What does it connect?
Autonomic ganglia transmit action potential originating in the CNS to the PNS; connects preganglionic neuron to post ganglionic neuron
From which specific site with in the CNS does the perganglionic fiber originate?
Either the lateral horn neurons in the spinal cord, or a cranial nucleus in the brainstem
What division of the autonomic nervous system do the paravertebral ganglia belong to?
Sympathetic
Where is the paravertebral ganglia?
Adjacent to both sides of the vertebral column from the cervical to coccygeal level
From which segments of the spinal cord do preganglionic neurons originate?
Thoracic and lumbar regions
Which division of the autonomic nervous is referred to as the “thoracolumbar division,” and which one is known as the “craniosacral division”?
Thoracolumbar division is associated with the sympathetic nervous system, and the craniosacral division is associated with the parasympathetic nervous system, depending on the region from which the preganglionic fiber emerges.
When considering cranial reflexes involving cranial nerves III, VII, IX and X, which division the autonomic nervous system primarily controls theses reflexes?
The parasympathetic nervous primarily controls these reflexes. In this reflex arc, the preganglionic neuronal cell body is located in cranial nuclei within the brainstem, rather than the spinal cord.
Which of the two divisions of the ANS possesses shorter preganglionic axons?
Pre-ganglionic is shorter in the sympathetic nervous system; post-ganglion is shorter in the parasympathetic nervous system