It’s the first answer choice :)
Answer:
A disadvantage of artificial selection is that it reduces the variation in a certain species.
Heterocyst-forming cyanobacteria differentiate highly specialized cells to provide fixed nitrogen to the vegetative cells in a filament. In the presence of a source of combined nitrogen such as nitrate or ammonium, Anabaena PCC 7120 grows as long filaments containing hundreds of photosynthetic vegetative cells.
The answer is <span>Special RNA polymerase, peptidoglycan in cell walls, ester-linked fatty acids.
Bacterial cell wall consists of peptidoglycans, not of cellulose or chitin. They also have ester-linked fatty acids, like eukaryotes. Ether-linked fatty acids are characteristics of Archaea. Also, bacteria have special RNA polymerase, unlike Eukaryotes that have three different type of RNA polymerase.</span>