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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Responsible for rest-and-digest, the parasympathetic division of the autonomic nervous system will be handling the body’s after-dinner activities.
Organ: Stomach and intestines
Major nerve supply: vagus (X) nerve
Effect of the parasympathetic nervous system: Increased motility and tone; relaxation of the sphincters
Organ: Liver
Major nerve supply: vagus (X) nerve
Effect of the parasympathetic nervous system: synthesis of glycogen; increased secretion of bile
Organ: Gallbladder
Major nerve supply: vagus (X) nerve
Effect of the parasympathetic nervous system:
Organ: Pancreas
Major nerve supply: vagus (X) nerve
Effect of the parasympathetic nervous system: secretion of insulin and digestive enzymes
Organ: Heart
Major nerve supply: vagus (X) nerve
Effect of the parasympathetic nervous system: Decreased heart rate and force of atrial contraction
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?
During such stressful and dangerous situations/emergencies, the body’s sympathetic nervous system facilitates our quick involuntary responses. It detects the danger and stress to enable our body to quickly react. With this, the sympathetic nervous system directs hormones to increase heart rate, activate sweat glands, and show visible goosebumps. These bodily reactions are involuntary and help our body to be more alert as the sympathetic nervous system controls our fight-or-flight response.