The part of the CNS that is responsible for these functions is the brain stem.
The brain stem is the part of the brain that control very basic functions of your organism and lets them work together as they should. The other parts that are mentioned all have much more specific and also different roles.
Because it carries a lot of blood to the arteries
<span>Positive Homans'
medical Definition of Homans' sign. : pain in the calf of the leg upon dorsiflexion of the foot with the leg extended that is diagnostic of thrombosis in the deep veins of the area.</span>
The question is unclear, is there more to it?
I cannot answer this question without knowing the circumstances, but it is good to remember that mutualism is where both species and/or participants benefit, and parasitism is where one species benefits and the other one is harmed.
Think of mutualism like the word mutual, so when people say " the feeling is mutual" it means that both parties feel and/or express the same feelings. Parasitism should be thought of like a parasite. When one is infected or has contracted a parasite, the parasite will live off of its host body making it ill or even causing death as it drains resources from its host to benefit itself.
