Bacteria in the phylum occur as elementary or reticulate bodies depending on their life cycle stage, are obligate intracellular parasites, and also have relatively small genomes.

This question lacks options, options are:

Chlamydiae

Planctomycetes

Rickettsia

Bacteroidetes

The correct answer is Chlamydiae.

Explanation:

Chlamydiae together with mycoplasmas, constitute the bacterial species with the smallest genomes, possibly because they are obligate small intracellular parasites for a long time, which has allowed them to lose certain metabolic pathways, however, they contain DNA, RNA and ribosomes therefore synthesize their own proteins and nucleic acids. Chlamydiae have a unique biphasic life cycle: the elemental body, which is the infectious form, and the reticular body, which is the replicative and metabolically active form that possesses a fragile membrane that lacks the extensive disulfide bonds characteristic of elemental bodies. The characteristics of its biological cycle do not facilitate the possibility of exchange and acquisition of exogenous genetic material.

maritime tropical may be your answer.

they fuse to form they have half as many chromosomes as a somatic cell of the same individual. b