You are observing a sample of cells in the lab to determine why they did not divide?

Plasma, which makes up about half of the blood’s total volume, is an especially profitable blood component. Since plasma has none of the cellular blood parts—red cells, white cells, and platelets—it can be dried and stored
The cell nucleus is found only in eukaryotic cells. The cellnucleus is the control center of the cell and DNA is found insidethe nucleus in the form of chromosomes.. It is the site of transcription of genes directed by the needsof the cell.
Centrioles or centrosomes are present only in animal cells; absent in plant cells (except fungal cells) & prokaryotes. Cytoplasm is found in eukaryotic and prokaryotic cells. It exists within the plasma membrane, which is a structure that encloses the cell's contents. The plasma membrane is a three-dimensional object that connects to and supports other cell component located near nucleus.

I hope his information is helpful. The Centrioles are present only in animal cells. This may be the solution.
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