Cell theory states: all living things are composed of one or more cells; a cell is the smallest unit that still retains the properties of life; and new cells only come from cells that already exist. based on cell theory, why is a virus considered non-living? a) a virus does not have a nucleus. b) a virus does not contain genetic material. c) a virus is too small to be considered a cell. d) a virus cannot reproduce itself without a host cell the members of these kindoms all have cell walls. which kingdoms are they? a) eubacteria, archaebacteria b) protists, fungi, plants, animals c) eubacteria, archaebacteria, plants, fungi d) eubacteria, archaebacteria, protists, animals membrane-bound organelles are not found in the cells of \ a) bacteria. b) fungi. c) plants. d) protists.