Which of the following cells possesses only a single outer membrane?

Statement $P$: The middle lamella is composed of cellulose plates.
Statement $Q$: During the formation of gametes,cell division occurs by mitosis.

$i.$ The shape of the cells may vary with the function they perform.
$ii.$ Human $RBC$ is about $7.0 \, \mu m$ in diameter.
$iii.$ Cytoplasm is the main arena of cellular activities.
$iv.$ Various chemical reactions occur in cytoplasm to keep the cell in the living state.

Prokaryotic cells do not have:

According to the modern colloidal theory,the cytoplasm is a polyphasic colloidal system. Who first proposed this?

Mitochondria and chloroplasts:
$(a)$ Are semi-autonomous organelles.
$(b)$ Are formed by the division of pre-existing organelles. They contain $DNA$,but lack protein-synthesizing machinery.
Which of the following options is correct?