Question

The golgi apparatus works like a mail room by receiving and sending what?

Answer 1

proteins

The Golgi apparatus works like a mail room. The Golgi apparatus receives proteins from the rough ER and puts "shipping addresses" on them. The Golgi then packages the proteins into vesicles and sends them to the right place in the cell or to the cell membrane. Some of these proteins are secreted from the cell  they exit the cell ; others are placed into the cell membrane.