1 The kidneys are used to remove excess water and ions from the blood. 2  These are then expelled as urine. 3  The kidneys perform a vital role in homeostatic regulation in mammals, removing excess water, salt, and urea from the blood.
Ectoparasites Parasites that live on the outside of the host, either on the skin or the outgrowths of the skin, are called ectoparasites. They are directly transmitted between hosts.
1. papilla - (botany) a tiny outgrowth on the surface of a petal or leaf. appendage, outgrowth, process-a natural prolongation or projection from a part of an organism either animal or plant; a bony process. phytology, botany-the branch of biology that studies plants.. papilla-a small projection of tissue at the base of a hair or tooth or feather. appendage, outgrowth, process-a natural prolongation or projection from a part of an organism either animal or plant; a bony process.