Diagram of endoplasmic reticulum includes structures like Rough Endoplasmic Reticulum (RER), Smooth Endoplasmic Reticulum (SER), Ribosomes, Membrane-bound vesicles, and Tubules. The Endoplasmic Reticulum (ER) is a complex system of tubes found solely in the cytoplasm of eukaryotic cells. We can learn about its structure with the help of a diagram of the endoplasmic reticulum easy way.

The diagram of the endoplasmic reticulum with labeling is given below:

Diagram of the Endoplasmic Reticulum

What is Endoplasmic Reticulum?

The endoplasmic reticulum (ER) is a complex network of tubes and compartments located within cells. It is critical for several cell functions, including protein synthesis, lipid breakdown, calcium storage, and toxin removal. There are two types of endoplasmic reticulum: Rough endoplasmic reticulum and Smooth endoplasmic reticulum. It is absent in prokaryotes cells but found in all eukaryotic cells, except for mammalian red blood cells and germinal cells.

Types of Endoplasmic Reticulum

There are 2 types of endoplasmic reticulum:

1. Rough Endoplasmic Reticulum
2. Smooth Endoplasmic Reticulum

Rough Endoplasmic Reticulum

The rough endoplasmic reticulum (RER) is composed of layers of phospholipids, similar to the structure of the cell’s outer barrier, the plasma membrane.

• The RER takes its name from its appearance.
• It is composed of flat sacs that are linked together and covered with many ribosomes on the outside.
• RER is responsible for the production and release of proteins such as hormones and chemicals in the liver and certain glands.
• Cells with a high protein need, such as liver cells (hepatocytes), have a very rough ER.
• The RER is primarily responsible for protein synthesis.
• It’s critical for folding the proteins into the appropriate structures.
• It also ensures that proteins are appropriately folded, similar to a quality check.
• After producing and folding proteins, RER is responsible for sorting them into the proper locations inside the cell.

Smooth Endoplasmic Reticulum

The SER is similar in structure to the RER except for the absence of the ribosomes. It consists of a network of tubes and flattened sacs.

• The SER lacks ribosomes.
• It is shaped more like tubes.
• The smooth ER contributes to the production of phospholipids, which are essential for cell membrane formation and metabolism.
• It also transports materials produced in the rough ER to other areas of the cell, such as the Golgi apparatus.
• The SER synthesises essential fats such as phospholipids and cholesterol.
• It also produces and secretes hormones called steroids.
• SER contributes to the breakdown of carbs.
• It accumulates and releases calcium ions, which are essential for the nervous system and muscles to function properly.

Also Read: Difference Between Smooth and Rough Endoplasmic Reticulum

What is the Structure of Endoplasmic Reticulum?

The structure of ER includes a membrane of approximately 50 to 60 angstroms thick and has a fluid-mosaic structure similar to the plasma membrane. It connects to the plasma membrane, the membrane surrounding the nucleus, and the membranes of the Golgi apparatus. Inside the endoplasmic reticulum, there is a region that serves as a conduit for secretions. The endoplasmic reticulum contains few components like: