Video Transcript
Which of the following statements
correctly describes the difference between the sympathetic and the parasympathetic
nervous systems? (A) The sympathetic nervous system
prepares the body for strenuous activity and the fight-or-flight response, whereas
the parasympathetic nervous system conserves energy and regulates the
rest-and-digest state. Or (B) the sympathetic nervous
system conserves energy and regulates the rest-and-digest state, whereas the
parasympathetic nervous system prepares the body for strenuous activity and the
fight-or-flight response.
The autonomic nervous system has
two parts: the sympathetic and parasympathetic nervous systems. These two systems oppose one
another and are used for different functions. The sympathetic nervous system
takes over when the body is undergoing a stressful or strenuous situation. It causes many physiological
changes, including dilating the pupils, increasing heart rate, and stimulating the
secretion of sweat and release of adrenaline hormones. This is known as the
fight-or-flight response, in which the body is preparing to deal with exertion and
stress.
The parasympathetic nervous system
does exactly the opposite. It takes over when the body is in a
restful state. It conserves energy, favors
sleepiness by constricting the pupils, and increases blood flow to nonvital systems
such as the digestive tract. This is known as the
rest-and-digest state. So the answer that correctly
defines these two systems is (A). The sympathetic nervous system
prepares the body for strenuous activity and the fight-or-flight response, whereas
the parasympathetic nervous system conserves energy and regulates the
rest-and-digest state.
