What part of the cell is responsible for packaging and sending proteins?

The Golgi apparatus, or Golgi complex, functions as a factory in which proteins received from the Endoplasmic Reticulum are further processed and sorted for transport to their eventual destinations: lysosomes, the plasma membrane, or secretion.

Mitosis is important for a number of reasons. It's a form of reproduction for some organisms that reproduce asexually, it's needed for growth and development, and also for the repair and replacement of cells. If we didn't do mitosis dead cells wouldn't be replaced, and that would cause some massive problems. For example, if we weren't capable of doing mitosis and you cut your hand, the cut wouldn't heal up because the cells wouldn't be getting replaced.