3 Parts of a Cell

              Three parts of a cell are a nucleus, a cell membrane, and ER. These are only some parts of a cell, since there are a lot more parts in there. A nucleus is basicallythe brain of the cell and is the one who will tell each of the organelles what to do. A cell membrane is a gate that blocks what is bad outside a nd lets better things in. It is really a gate that allows or doesn't allow something in to the cell. These help keep things inside the cell like organelles from getting out and keeps other harm for matter from coming in. The ER is short for endoplasmic reticulum and is like a channel of tunnels throughout the cell that transport protien. There are two kinds of endoplasmic reticulum; rough and smooth. The rough endoplasmic reticulum has ribosomes attached on to the inside of it.