How do the rough endoplasmic reticulum and the Golgi apparatus act in the production and releasing of proteins?
The rough endoplasmic reticulum has in its outer membrane many ribosomes, structures where translation of messenger RNA and protein synthesis happen. These proteins are kept in the rough endoplasmic reticulum and later they go to the Golgi apparatus. Within the Golgi apparatus proteins are chemically transformed and when ready they are put inside vesicles that detach from the organelle. These vesicles fuse with the plasma membrane (exocytosis) in the correct place and its content is liberated outside the cell.