2.85 Understand that stimulation of receptors in the sense organs sends electrical impulses along nerves into and out of the central nervous system, resulting in rapid responses

Electrical impulses are sent from receptors in sense organs when there is a stimulus to the CNS. They are then sent straight back (after a response has been decided) through nerves to the effector. This has a sort of reflex-arc effect. 

(I wrote this in purple because I felt like it)