Why a mastectomy may be necessary. A mastectomy is mainly used as a treatment for breast cancer or to reduce the risk of breast cancer developing. Although breast cancer in men is much rarer than female breast cancer, it can also be treated with a mastectomy. Treating breast cancer.
Bacteria. The Bacteria are considered as unicellular prokaryotic organisms. Unlike eukaryotes, bacteria cells lack an organized nucleus, mitochondria, chloroplasts and other membrane bounded organelles. Bacterial cell has only a circular DNA, which does not associate with histone protein.Bacteria do not show sexual reproduction methods.nlike eukaryotes, bacteria cells lack an organized nucleus, mitochondria, chloroplasts and other membrane bounded organelles. Bacterial cell has only a circular DNA, which does not associate with histone protein. Bacteria do not show sexual reproduction methods.
These remarkable organisms are now placed in the domain Archaea. Other prokaryotes, including eubacteria and cyanobacteria, are placed in the domain Bacteria. All the kingdoms of eukaryotes, including Protista (Protoctista), Fungi, Plantae and Animalia, are placed in the domain Eukarya.The large molecular differences between the majority of prokaryotes in the kingdom Monera and the archaebacteria warrants a separation based on categories above the level of kingdom. iving organisms are subdivided into 5 major kingdoms, including the Monera, the Protista (Protoctista), the Fungi, the Plantae, and the Animalia. Each kingdom is further subdivided into separate phyla or divisions.