Answer: In fact, some viruses have beneficial properties for their hosts in a symbiotic relationship (1), while other natural and laboratory-modified viruses can be used to target and kill cancer cells, to treat a variety of genetic diseases as gene and cell therapy tools, or to serve as vaccines or vaccine delivery agents.
Explanation:
Rocky , made of gas , low density , small
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Answer: The correct answer is- B)They are single cells that lack a nucleus and tend to live in extreme conditions.
Archaebacteria are the oldest life forms, which are found on earth. They are unicellular ( made up of one cell) prokaryotes ( lacking nucleus and membrane bound subcellular organelles) belonging to the kindom, Archea. They are found in extremely harsh environmental conditions such as hotsprings, boiling mud surrounding volcanoes.
Example- Methanogens, halophiles.
Thus, option B) is the right answer.
