Answer:
Oxygen
Explanation:
The formula for cellular respiration is oxygen + glucose -> water, carbon dioxide, energy. You can already cross out A and D because they aren't in the formula, so you have two left, water and oxygen. The reason why it is oxygen and not water is because without oxygen you can't even have water. also, I just got this right on my test :-)
Because neurones will not function properly neither will neuroreceptors if a person lacks neurotransmitters, these two parts (transmiters and receptors) all work together and depend on eachother.
Neurones are resposible for transmitting informations trought the body, and if neurotransmitters are no-existent, information may not be able to get to some body parts since neurotransmitters transmit the information.
Hope it helped,
Happy homework/ study/ exam!
