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.
Cladistics is a particular systematic scheme based on an explicit theory of evolution. In cladistics., organisms inherit their genes through meiosis or mitosis (so it applies to sexual and asexual organisms). This is the basis for the focus on ancestry as linking organisms into groups.he first, phenetics, is not a systematic approach (that it, based on relatedness), but the second one, cladistics, is systematic. Pheneticists approach taxonomy by measuring as many characteristics of each individual as possible.