The term that is being referred to in the given item above is essential lipid which other may more fondly refer to as essential fatty acids. These essential substances are mostly needed for the maintenance and integrity of the cellular membranes to be able to do their functions.
It disappears from existence completely, idk. ask your teacher. hope this helps!
Metabolic pathways stimulate cell division.
If there where a decrease in the number of decomposers there would be a increase in the number of producers and consumers.