Which of the following statements is incorrect?

Eukaryotic cells have a well-organized nucleus and:
$a$. Both $70S$ and $80S$ types of ribosomes
$b$. Flagella associated with $9+2$ organization
$c$. Shows cytoplasmic streaming
$d$. Their $DNA$ is complexed with histones to constitute the chromatin

Which stain is used for electron microscopy?

Identify the components labelled $A, B, C$ and $D$ in the diagram below from the list $(i)$ to $(viii)$ given along with:
Components:
$(i)$ Cristae of mitochondria
$(ii)$ Inner membrane of mitochondria
$(iii)$ Cytoplasm
$(iv)$ Smooth endoplasmic reticulum
$(v)$ Rough endoplasmic reticulum
$(vi)$ Mitochondrial matrix
$(vii)$ Cell vacuole
$(viii)$ Nucleus
The correct components are:

Which of the following organelles is not a part of the endomembrane system?

What are $P, Q,$ and $R$ in the given plant cell?