What system passes information from external stimuli to the nervous system?

The answer is sensory neurons. They have receptors on the epithelial tissue. Also referred to as afferent neurons, they convert stimuli from the environment into an impulse that is transmitted to the Central Nervous System for interpretation and for a response signal through the efferent /motor neurons.

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d

a symbiotic relationship with the mitochondria