1. Viruses, virions and prions have no cellular location.
2. Bacteria, archaebacteria and blue-green algae do not have a well-structured nucleus.
3. Many algal and fungal cells are multinucleated.
4. The protoplasm of many cells is dead.
5. Red blood cells and cytoplasm are without nucleus.
6. Connective tissue contains a lot of extracellular matrix.