Ms. brown's class looked at their cheek cells using microscopes. they stained the cells before using the microscopes. without using the microscopes, they would not be able to see the cell organelles, like the which is seen as a dark blue spot in the center of each cell.

Nucleus, is always at the center of an cell

Cell nucleus.

Explanation:

The cell's nucleus consists of the cell's genome and a small part of the DNA and holds a large variety of the proteins which are used to form the chromosomes and promote the cell function and is at the center and regulate the gene expressions. Therefore the nucleus is the largest organelle in the cell occupying 10% of the cell volume.

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