Yes, onion cells have a nucleus.
Onion cells, like most eukaryotic cells, contain a distinct nucleus that houses the cell's genetic material (DNA). The nucleus is a membrane-bound organelle responsible for controlling and regulating cellular activities such as growth and metabolism. It directs protein synthesis and contains the hereditary information passed on during cell division. The presence of a well-defined nucleus is a key characteristic of eukaryotic cells, distinguishing them from prokaryotic cells, which lack a nucleus. In observing onion cells under a microscope, the nucleus is typically visible as a darker, spherical or oval structure within the cell. The surrounding cytoplasm and other cell structures, such as the cell wall and vacuole, are also visible.
