# What is the nucleolus?

May 2, 2015

The nucleus is one of the most important cell organelles.

Most of the cells have in their nucleus, one or more $\textcolor{b r o w n}{s p h e r i c a l}$ colloidal bodies, this is the nucleolus.

They are dense and prominent.

• They are associated with synthetic activity and are sites of biogenesis of $\textcolor{p u r p \le}{r i b o s o m a l}$ subunits.

• The nucleolus contain $\textcolor{B L U E}{D N A}$ and $\textcolor{B L U E}{R N A}$.

• The appearance of the nucleolus changes during different phases of the cell cycle.