What cell structure is responsible for packaging and distributing proteins?

The Golgi apparatus is the cell structure responsible for packaging and distributing proteins. After proteins are synthesized by ribosomes, they are transported to the Golgi apparatus, where they undergo further modifications, such as glycosylation. This organelle functions like a post office, receiving proteins from the endoplasmic reticulum (ER) and sorting, modifying, and packaging them into vesicles for transport to their final destinations, which may include secretion outside of the cell or delivery to other organelles.

The other choices represent different cell structures with distinct functions. Ribosomes are primarily responsible for protein synthesis, while the nucleus serves as the control center of the cell that houses DNA. Chloroplasts are involved in photosynthesis, converting light energy into chemical energy in plant cells. Each of these structures plays a vital role in cellular function, but the Golgi apparatus specifically focuses on the packaging and distribution of proteins.