National Certified Addiction Counselor, Level 2 (NCAC II) Practice Exam Exam

Which system of the autonomic nervous system is activated to increase heart rate and breathing?

1. Sympathetic Nervous System

2. Parasympathetic Nervous System

3. Central Nervous System

4. Motor Nervous System

The correct answer is: Sympathetic Nervous System

The sympathetic nervous system is responsible for the body's "fight or flight" response, which is activated during stressful or emergency situations. When this system is engaged, it leads to various physiological changes to prepare the body for action. One of the key responses is an increase in heart rate and breathing rate, which helps to supply more oxygen to the muscles and brain, enhancing physical performance. Additionally, the sympathetic nervous system triggers the release of adrenaline (epinephrine) and norepinephrine from the adrenal glands, further amplifying these effects. This response is crucial for survival as it equips the body to respond quickly to perceived threats or challenges. In contrast, the parasympathetic nervous system works to calm the body down after the stressor has passed, decreasing heart rate and promoting rest and digestion. The central nervous system encompasses the brain and spinal cord and serves as the main processing center for information, while the motor nervous system involves the generation of movement through the control of skeletal muscles. Thus, the sympathetic nervous system's activation leads directly to the increase in heart rate and breathing, aligning perfectly with the mechanism of response to stress or danger.