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.
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The division of the nervous system that will be handling the body’s after-dinner activities is the parasympathetic division.
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The organs, the major nerve supply and the effects of the nervous system on their functions:
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Salivary glands
- Major nerve supply: Facial nerve (VII)
- Effects: It controls saliva production and stimulates saliva flow.
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Lungs
- Major nerve supply: Vagus nerve (X)
- Effects: It controls respiration as well as pulmonary function. It also tightens the bronchi.
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Heart
- Major nerve supply: Vagus nerve (X)
- Effects: It regulates heart rate.
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Stomach
- Major nerve supply: Vagus nerve (X)
- Effects: It secretes gastric acid that digests proteins, which increases gastric secretion and motility.
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Pancreas
- Major nerve supply: Vagus nerve (X)
- Effects: It secretes insulin, glucagon and pancreatic juice.
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Liver
- Major nerve supply: Vagus nerve (X)
- Effects: It detoxifies metabolites and regulates the body's metabolism. It also produces chemicals that are needed for digestion.
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Small and large intestines
- Major nerve supply: Vagus nerve (X)
- Effects: These absorb nutrients and stimulate secretion and digestion.
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Gallbladder
- Major nerve supply: Vagus nerve (X)
- Effects: It releases and stores bile, which helps in the digestion of food.
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Rectum
- Major nerve supply: Pelvic nerve
- Effects: It stores the deposited feces until they are eliminated through defecation.
https://my.clevelandclinic.org/health/body/23266-parasympathetic-nervous-system-psns (Parasympathetic Nervous System (PSNS): What It Is & Function, 2022)
https://www.healthline.com/health/fun-facts-about-the-nervous-system#4 (Cirino & Sabogal, 2019)
http://gastrodigestivesystem.com/digestion/parasympathetic-nerves
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?
This type of experience is related to the sympathetic nervous system, often known as the body's fight-or-flight response. The amygdala is the portion of the brain that initiates the response. It is essential in the processing of emotions, including fear. A fight-or-flight response was demonstrated by the abrupt swerve to avoid collision with the bicycle. Increased heart rate, goosebumps, and perspiration are just a few of the body's fear responses to someone who has nearly been in an accident.
https://www.medicalnewstoday.com/articles/323492#Triggering-the-response (Newman & Lali, 2021)