If you are reading and you unexpectedly hear a loud noise, your head generally snaps up. which portion of the midbrain is most likely to be responsible for this reflexive motion? a. the inferior colliculus b. the superior colliculus c. the red nucleus d. the substantia nigra

The answer is A: The Inferior Colliculus

Explanation:

The inferior Colliculi play a major role in hearing. Since the loud noise was what prompted the response it is safe to say the inferior Colliculi is responsible.

Neurons in the inferior Colliculi respond to cues such as intensity, the difference red in arrival of sound to both ears.

However, the head snaps up because the information from the inferior Colliculi is transmitted to the superior Colliculi which is involved with movement such as the head.

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.