Answer:
TRUE
Explanation:
No biological system is completely closed.
A nutrient cycle is the movement and exchange of both organic and inorganic matter back into the production of matter. This cycle is a recycling system which always occurs no matter what.
In a system that looks closed (closed loop), nutrients may be limited because they are not cycled through the system fast enough and/or it is not possible to compensate for deficiencies by migration.
Not sure if you still need the answer but its number Three, they are the decomposers in many ecosystems
A procaryotic cell has five essential structural components: a nucleoid (DNA), ribosomes, cell membrane, cell wall, and some sort of surface layer, which may or may not be an inherent part of the wall.
When stem cells grown on hard, rigid surface, then they became bone cells. Researchers demonstrate in Nature materials that human mesenchymal stem cells grown on a rigid substrate for some time become biased toward differentiating into bone-cell lineage, whereas cell grown on softer surfaces are just likely to eventually follow a bone or fat cell fate.