Which of the following is not a part of the nucleus? 

The nucleus is a crucial organelle in eukaryotic cells that contains genetic material in the form of DNA. It is composed of several components that perform specific functions. Chromatin is a complex of DNA and histone proteins that make up the genetic material in the nucleus. The nucleolus is a distinct structure within the nucleus that is involved in the synthesis of ribosomes. The nucleoplasm is the liquid substance that fills the nucleus and surrounds the genetic material.

The centrosome, on the other hand, is not a component of the nucleus. It is an organelle that is involved in cell division and is located outside of the nucleus. The centrosome is responsible for organizing the microtubules that form the spindle fibers during cell division.