Cleaving a flatworm into pieces would not kill the flatworm as each piece would turn into a new flatworm. The mechanism is known as fragmentation. In multicellular species, fragmentation refers to a kind of asexual reproduction in which a species gets cleaved into fragments.
Each of these fragments forms into completely developed, mature individuals, which are similar to their parents. Fragmentation is also called splitting, it is a mode of reproduction witnessed in various species like molds, filamentous cyanobacteria, lichens, various plants, and animals like flatworms, sponges, sea stars, and some annelids.
A common theme in biology is that energy flows through biological systems while matter IS RECYCLED. Energy and matter are not destroyed in the ecosystem. The energy is transformed and the matter is recycled. In a food web, the food is transferred from one organism to another in different forms. this shows that the same molecules and atoms are recycled as the same molecule is used by one organism and then transferred to the second organism.
Maritime polar, North Atlantic Ocean
The oceans, lower atmosphere, and continents are parts of the biosphere.
The biosphere is composed of the parts of planet Earth where life exists and it is the total of all the ecosystems. The biosphere along with lithosphere (rock), hydrosphere (water) and atmosphere (air) are the four layers that surround the earth. The biosphere covers a wide area from the deepest root systems of trees, to rainforest, to the ocean depth and high mountaintops. The biosphere contains living organisms and nonliving things from which they obtain energy and nutrients.
It's the presence or absence of a surrounding membrane
