Answer:
effector
Explanation:If the value is not at the set point or is outside the normal range, the control center sends a signal to the effector. The effector is an organ, gland, muscle, or other structure that acts on the signal from the control center to move the variable back toward the set point.
Ingestion<span> - the process of taking food into the body through the mouth (as by eating) consumption, intake, uptake.
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Hundreds or thousands of years.
It illustrates the cycling of matter, just like in a natural ecosystem.
Option D.
<h3><u>Explanation:</u></h3>
The natural stable ecosystem is defined as the ecosystem which has the members doing their part of job and each and every member contribute to the stability of the ecosystem by completing food chains.
Here in this bottle ecosystem the boy put the stones, rocks, water which gives proper nutrition to the growing plants and animals which are also introduced by the boy. The plants produce oxygen and consume carbon dioxide whereas the animals consume oxygen and produce carbon dioxide. Thus the cycle is maintained and stability is achieved.