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 stimulation of the parasympathetic nervous system controls digestion and relaxation. Listed below are the organs involved in the said activities, its major nerve supply, and the effects of the nervous system on its functions.
Organ: Salivary Glands
Major Nerve Supply: Facial (VII) nerve and glossopharyngeal (IX) nerve
Effects of the nervous system on their functions: Increased saliva secretion
Organ: Pancreas
Major Nerve Supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased secretion
Organ: Liver
Major Nerve Supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased secretion of digestive enzymes
Organ: Stomach
Major Nerve Supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased activity
Organ: Gallbladder
Major Nerve Supply: Vagus (X) nerve
Effects of the nervous system on their functions: Increased contractions
Organ: Intestines
Major Nerve Supply
Effects of the nervous system on their functions: Increased activity
Organ: Heart
Major Nerve Supply: Vagus (X) nerve
Effects of the nervous system on their functions: Decreased force and rate of heart contractions
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 situation Ciara has experienced triggered the fight-or-flight response, causing an increased sympathetic activity and providing her body with a burst of energy. The system’s activity heightens when one is stressed, in danger, or physically active to respond to perceived dangers by sensory organs that sends the information to the amygdala. The amygdala interprets information and sends a distress signal to the hypothalamus, which, in turn, sends signals to adrenal glands through autonomic nerves. It triggers the secretion of epinephrine and norepinephrine into the bloodstream. This causes an increased heart rate, sweating on the palms, and contraction of the arrector pili muscles (goosebumps).