Answer: A whale swimming in water is an example of matter cycling over the body of a living thing. In that as the whale swims water which is matter moves across its body.
Prothallus represents a gametophyte in the life cycle of fern.
A prothallium, or prothallus<span> (from Latin pro = forwards and Greek θαλλος (thallos) = twig) is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally the term is also used to describe the young gametophyte of a liverwort or peat moss as well.
so the answer should be prothallus</span>
