Muscle cramps, fatigue, headaches, decreased ability to excrete toxins/waste from the body or carry nutrients throughout the body dryness, wrinkles, etc
A community is diverse species living together
An Ecosystem is all the living and nonliving factors that affect an organism
From my knowledge I mostly think its Thalilacea
I think this because even though it can be Appendicularia too, Thalilacea has BOTH a tail and notochord in the adult stage