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.
the cell membrane is the semi-permeable protective cover that keeps the cell held together. the cytoplasm is semi-fluid within the cell membrane that keeps the cell in shape.
What is the mechanical advantage of a lever that has an input arm of 3 meters and an output arm of 2 meters? 3. A lever with an input arm of 2 meters has a mechanical advantage of 4.
