$A$ polyribosome is formed by the arrangement of which of the following?

The eukaryotic $80S$ ribosome dissociates into which two subunits?

Which of the following cell organelles is known as the protein factory?

From the statements given below,choose the correct option:
$A.$ The eukaryotic ribosomes are $80S$ and prokaryotic ribosomes are $70S$.
$B.$ Each ribosome has two sub-units.
$C.$ The two sub-units of $80S$ ribosome are $60S$ and $40S$,while those of $70S$ are $50S$ and $30S$.
$D.$ The two sub-units of $80S$ ribosome are $60S$ and $20S$,and those of $70S$ are $50S$ and $20S$.
$E.$ The two sub-units of $80S$ ribosome are $60S$ and $30S$,and those of $70S$ are $50S$ and $30S$.

$DNA$ is not present in:

Which of the following statements is true regarding ribosomes?