When a cell surrounds a large particle with pseudopodia and then engulfs it, the process is called?

I believe this is called phagocytosis. Phagocytosis is a form of endocytosis in which a cell surrounds a foreign particle with pseudopods and engulfs it, enclosing it in a cytoplasmic vessicle called phagosome. The process is meant to either destroy the foreign material, to feed on it, or to get information from it.

Nucleus is the organelle that contains chromosomes

The combined mass of both