The Cell
In eukaryotic cells a nuclear envelope separates the contents of the nuclear compartment from the cytoplasm. The nucleus is the storage place for DNA and the location for its transcription. The nucleus is basically the same in all cells; the cytoplasm varies in cells specialized for different tasks. When not dividing the interphase nucleus of most cells has common components though there are variations among cells.
The cytoplasm carries out most of the cell’s principal activities and so is specialized by the presence of different kinds of organelles which are suspended in the cytoplasmic matrix called cytosol. The internal support of the cytoplasm consists of a complex system of microtubules and microfilaments called the cytoskeleton.