Protections the ozone layer
Maintaining animal and human food chain
Preserving potable water and making efficient use of non renewable resources
<span>The control would be a plant grown without any fertilizer. This is called a negative control and is important in identifying the influence of the treatments on the tests. In this case, it would mean that the plant without fertilizer (control) is not expected to grow as large as in the other treatment. </span>
Answer: The correct answer is B) city hall:control center.
As per the question, model of cell looks like a city where different buildings correspond to different organelles ( membrane bound subcellular compartments like nucleus, golgi complex, vacuole, endoplasmic reticulum).
Nucleus is a specialized membrane bound compartment that possesses the genetic material ( DNA) of the Eukaryotes ( like plants and animals).
Nucleus controls all the essential activities of the cell by regulating the expression of gene ( segment of DNA corresponding to a particular protein).
Therefore, in the model of cell, city hall;control center represents the nucleus of the cell.
Centrioles is the organelle.