What is the difference in a nerve and the response it causes if it is defined as contralateral? ipsilateral?

A nerve produces a response on the opposite side from where it is coming then the response is called contralateral and if the nerve produces a response on the same side from where the nerve is coming then the response is called as ipsilateral.

Explanation:

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.