Dr. Cameron Answered First
Parenchyma is a term that means the tissue itself, so brain parenchyma is the part of the brain that is the brain itself, not its blood vessels, nor its coverings, nor its support structures.

Does a parenchyma have a nucleus?

Parenchyma is the bulk of an organ. Cells have nuclei. Organs comprise tissues, which comprise cells, each of which has a nucleus (RBCs excepted.)

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