Dayton's pupils are dilated and his heart is pounding immediately after he gets terrified by a large groundhog running across his driveway after he parks his car. his nervous system is activated.

a) sympathetic
b) efferent
c) parasympathetic
d) afferent

sympathetic

Explanation:

The sympathetic division of the autonomic nervous system is responsible for preparing the body under stress or emergency conditions such as being terrified by a large groundhog. The neurons of the sympathetic nervous system trigger an increase in heart rate, breathing rate to increase the oxygen supply needed by body cells under stress conditions.

Other physiological responses generated by the sympathetic nervous system under stress conditions are dilation of the pupil, increased blood pressure, etc. The sympathetic nervous system generates these responses by stimulating the release of stress hormone from the adrenal medulla. These responses are together called fight or flight response.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.