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.
