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.
Archaea vs. Bacteria. Archaea and bacteria are both single-celled organisms that reproduce asexually and do not have a nucleus. Archaea belong to a kingdom of single-celled microorganisms that do not have a nucleus or other organelles.In the past, archaea were classified as bacteria, but now they are known to be a separate type of organism. The word archaea is derived from the Greek archaios, meaning ancient.rchaea vs. Bacteria. Archaea and bacteria are both single-celled organisms that reproduce asexually and do not have a nucleus. Archaea belong to a kingdom of single-celled microorganisms that do not have a nucleus or other organelles.