4. The basic dichotomy of life
    a. Cell: is a membrane-bounded module with a variety of distinct features, including structures in which certain chemical reaction take place.
    b. Prokaryotic Cells (Domains Bacteria and Archaea
        Cells of the most primitive organisms have cells that lack a nucleus.
        Monerans (bacteria and related organisms) are prokaryotes.
        Prokaryotes also lack other membrane-bound internal structures.
    c. Eukaryotic Cells
        All organisms, other than monerans, have cells with nuclei.
        Cells with nuclei = eukaryotic cells, and the organisms made of such cells are eukaryotes.Eukaryotic cells have membrane-bound internal structures (organelles) in addition to the nucleus.Endosymbiosis: for the origin of the eukaryotic