Endoplasmic Reticulum

The Endoplasmic Reticulum is something called an ORGANELLE. You might know that inside your body there are different organs. You have a heart, kidneys, and a liver (each of those is an organ). A cell has the same thing going on. Scientists use the word organelle to describe a cell's different parts. The ER is one of those organelles inside the cell.

The Endoplasmic Reticulum is something called an ORGANELLE. You might know that inside your body there are different organs. You have a heart, kidneys, and a liver (each of those is an organ). A cell has the same thing going on. Scientists use the word organelle to describe a cell's different parts. The ER (short for Endoplasmic Re-blah-blah-blah) is one of those organelles inside the cell.

IT'S ROUGH… AND SMOOTH! When you examine the ER you should know that you will find two different types. The ER is made up of membranes that are in the CYTOPLASM of the cell.

So what are those two types of ER? There is ROUGH ER and SMOOTH ER. Rough ER has bumps all over it (thus the name rough). These bumps are called RIBOSOMES. Rough and smooth ER are also different shapes. The rough is like sheets of cloth while smooth are slightly tubular.

WHAT THE ROUGH ONE DOES FOR YOU The purpose of the ER is to collect proteins. The ER collects the proteins (built by the cell) and creates a bubble around them. That bubble is called a VESICLE. The vesicle is formed when the ER pinches off a part of its membrane. The vesicle can then move to the Golgi apparatus or the cell membrane. If the vesicle floats to the cell membrane, the proteins are going to be sent out of the cell. If they move to the Golgi Apparatus, the proteins will be used inside the cell.

SMOOTH HAS ITS PLACE TOO Smooth ER creates something called steroids and stores ions. When the smooth ER stores those ions it is so that the cell can keep the correct levels of nutrients. That ion storage is like your body's fat cells holding onto sugars just in case you need them. The thing to remember is that the smooth ER collects things and contains them. ¹⁾

The endoplasmic reticulum (ER) is a large, dynamic structure that serves many roles in the cell including calcium storage, protein synthesis and lipid metabolism. The diverse functions of the ER are performed by distinct domains; consisting of tubules, sheets and the nuclear envelope. Several proteins that contribute to the overall architecture and dynamics of the ER have been identified, but many questions remain as to how the ER changes shape in response to cellular cues, cell type, cell cycle state and during development of the organism. Here we discuss what is known about the dynamics of the ER, what questions remain, and how coordinated responses add to the layers of regulation in this dynamic organelle. Keywords: Interphase, Mitosis, Unfolded protein response, Organization, Fertilization, Phosphorylation ²⁾