Which of the following processes occurs in the nucleus of $PPLO$?

Infoldings of the plasma membrane of gram-positive bacteria give rise to:

Select the correct option for the following statements:
$(i)$ The living cytoplasmic structures are called cell organelles / cell inclusions.
$(ii)$ Nucleoid is found in prokaryotic / eukaryotic cells.

An undefined or undifferentiated fibrillar nucleus is seen in

Mitochondria are non-existent in

Which of the following statements about a bacterial cell is/are correct?
$(i)$ Mesosome is formed by the extensions of plasma membrane into the cell.
$(ii)$ The pili are elongated tubular structures made up of a protein.
$(iii)$ Flagellum is composed of filament,hook,and basal body.
$(iv)$ Ribosomes are about $30 \; nm$ by $50 \; nm$ in size.