The Digestive system.
The muscular system is involved in contractions and creating body heat.
The imune system
There are two: the digestive system and the cardiovascular system.
The Immune System. Sorry to disappoint.
Fundamentally the system involved in a reaction to a stimuli is the nervous system.
hair,skin
the digestive system
Respiratory system
nothing. Absolutely every part of your body is involved in the immune system. Having said this, not every part CONTRIBUTES to you immune system. I don't think that the muscular system really helps, but every other system does.
digestive system
i think its the circulatory system
nervous system, skeleton system, muscular system, digestive system