1. You have been to an ‘eat all you can’ buffet and have consumed large amounts of food. After returning home, you recline on the couch to watch television. Which division of the nervous system will be handling your body’s after-dinner activities? List several organs involved, the major nerve supply to each organ, and the effects of the nervous system on their functions.
The parasympathetic nervous system is responsible for handling the body’s after-dinner activities.
Some organs involved are:
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Salivary glands
Major nerve supply: Glossopharyngeal (IX) nerve
Effects of the nervous system on their functions: increased salivation; high volume potassium ions, water and amylase secretion
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Pancreas
Major nerve supply: Vagus (X) nerve
Effects of the nervous system on their functions: stimulates therelease of digestive enzymes and insulin
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Liver
Major nerve supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased bile secretion and glycogen synthesis
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Gallbladder
Major nerve supply: Vagus (X) nerve
Effects of the nervous system on their functions: stimulates contraction to release bile into the small intestine.
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Stomach and Intestines
Major nerve supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased motility and relaxation of sphincters; Stimulation of M receptors increases gastric secretion
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Rectum
Major nerve supply: Pelvic Splanchnic nerve
Effects of the nervous system on their functions: causes rectum contraction and relaxation of the anal sphincter to enable defecation
References
Browning, K. N., & Cannon, W. (2016, May 5). Central Nervous System Control of Gastrointestinal Motility and Secretion and Modulation of Gastrointestinal Functions. NCBI. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4858318/
Sendić, G. (2022, July 27). Parasympathetic nervous system: Anatomy and functions. Kenhub. https://www.kenhub.com/en/library/anatomy/the-parasympathetic-nervous-system
Tindle, J., & Tadi, P. (2021, November 5). Neuroanatomy, Parasympathetic Nervous System - StatPearls. NCBI. https://www.ncbi.nlm.nih.gov/books/NBK553141/
2. Your friend is driving home from work, listening to her favorite music, when suddenly a bicycle came out of nowhere. She manages to swerve avoiding hitting the bicycle. She continued to drive home but she noticed that her heart is beating fast, she had goose bumps, and her heads were sweaty. How would you explain these effects?
The sympathetic nervous system is responsible for the effects. The activation of the sympathetic division activates a series of physiological responses called “fight-or-flight” responses, which includes increased heart beat (to provide enough energy and oxygen to rapidly respond to danger) and sweating (since adrenaline activates sweat glands). The arrector pili muscles also have sympathetic innervation. Thus, explaining the involuntary response of goosebumps.
Tortora, G. J., & Derrickson, B. H. (2011). Principles of Anatomy and Physiology. Wiley.