As we all know, our body is made up of cells. In fact, All living beings are made up of cells. Some of them are made up of only one cell and others have many cells. Nucleus is one of the membrane bound organelles. Nucleus works as a brain of the cells because it It helps control eating, movement, and reproduction. So, the analogy for nucleus is the principal because what the principal does is to control all the things that's going on in the school and the principal is also a leader that'll take controls of any situations. Golgi Apparatus is basically the same as a teacher, because they have all the information or lessons that they studied before (or in the cell's case the ER). After all the Informations were delivered, they have to make sure that the students received the informations completely. Ribosome is the same as people who works in the cafeteria (cooks) because they give "proteins" to the students by making foods. DNA is like a library because DNA contains all the information necessary to build an entire living organism. A library also contains a lot of information. All the other organelles = customers, and Messenger RNA is the parent hand book or the "law" of the school