Emergency Medical Technician (EMT) Intermediate Practice Exam

What physiological response is triggered by the stimulation of the sympathetic nervous system?

1. Decreased heart rate and blood pressure

2. Increased blood pressure and heart rate

3. Relaxation of the bronchial muscles

4. Increased digestive activity

The correct answer is: Increased blood pressure and heart rate

The stimulation of the sympathetic nervous system triggers a "fight or flight" physiological response that prepares the body to react to stressful situations. This response is characterized by an increase in heart rate and blood pressure. When the sympathetic nervous system is activated, it releases neurotransmitters such as norepinephrine, which act on the heart to increase the rate and strength of contractions. Additionally, blood vessels may constrict during sympathetic activation, further contributing to the rise in blood pressure. This state enhances blood flow to vital organs and muscles, allowing the body to respond more effectively in emergencies. The other choices depict responses associated with different physiological states. Decreased heart rate and blood pressure typically happen during the activation of the parasympathetic nervous system, which promotes rest and digestion. Relaxation of the bronchial muscles suggests a calming response that would occur in the parasympathetic state, allowing for better airflow during non-stressful situations. Increased digestive activity also aligns with parasympathetic activation, which directs energy towards digestion rather than immediate survival responses seen with sympathetic stimulation.