name one organism that falls under this?
Frogs
Amphibian
Frog larvae are known as tadpoles and typically have oval bodies and long, vertically flattened tails with fins. 
what is referred to as oort cloud? A theoretical cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from 2,000 to 200,000 au from where did it originate? It is thought to have developed after the formation of planets from the primordial protoplanetary disc. what is it composed of? It consists of ices such as water, methane, ethane, carbon monoxide and hydrogen cyanide. what are the various states of the first one? solid phase, liquid phase, and the gaseous phase what kind of life form does it support? Nearly all fish, marine mammals, amphibians can you mention one characteristic of this last one? They are ectothermic, tetrapod vertebrates of the class Amphibia
wiki:1608248
Amphibian [SEP] Frogs
Frog larvae are known as tadpoles and typically have oval bodies and long, vertically flattened tails with fins. The free-living larvae are normally fully aquatic, but the tadpoles of some species (such as "Nannophrys ceylonensis") are semi-terrestrial and live among wet rocks. Tadpoles have cartilaginous skeletons, gills for respiration (external gills at first, internal gills later), lateral line systems and large tails that they use for swimming. Newly hatched tadpoles soon develop gill pouches that cover the gills. The lungs develop early and are used as accessory breathing organs, the tadpoles rising to the water surface to gulp air. Some species complete their development inside the egg and hatch directly into small frogs.