7. Regarding prokaryotic membrane extensions and surface structures, which statements hold true?
a) Mesosomes are infoldings of the cell wall.
b) Mesosomes help in respiration, secretion processes, and increasing surface area.
c) Chromatophores are pigment-containing extensions in cyanobacteria.
d) The bacterial flagellum is composed of filament, hook, and basal body.
e) Pili and fimbriae are the primary structures for motility.
f) Fimbriae are small, bristle-like fibres that can help in attachment to rocks or host tissues.
g) Pili are short structures made of a special protein.