Identify $X$ and $Y$ in the given figure.

Except for bacteria,what do all cells contain within their cell membrane?

Name two cell-organelles that are double membrane-bound. What are the characteristics of these two organelles? State their functions and draw labelled diagrams of both.

Which of the following statements are correct?
$(i)$ In prokaryotic cells,a special membranous structure formed by the extension of the plasma membrane into the cell is known as polysome.
$(ii)$ The smooth endoplasmic reticulum is the major site for synthesis of glycoproteins.
$(iii)$ $RuBisCO$ is the most abundant protein in the whole biosphere.
$(iv)$ Mitochondria,chloroplasts,and peroxisomes are not considered as part of the endomembrane system.

In the given hierarchy of biological organization: $(P) \rightarrow \text{Subatomic particles} \rightarrow \text{Atoms} \rightarrow \text{Molecules} \rightarrow (Q) \rightarrow \text{Cells} \rightarrow \text{Tissues}$,what do $(P)$ and $(Q)$ represent respectively?

Which of the following statements is incorrect?