One of the best ways to understand—and remember! In a manufacturing plant, people take raw materials and make it into something new and usable, which they then ship to other stores, manufacturers, and suppliers around the world. So what does the endoplasmic reticulum look like, exactly? Well, do you remember the mazes that you could find in coloring books when you were a kid? The endoplasmic reticulum looks a lot like that!
The cisternae stretch out and away from the cell nucleus in a series of folds and tubes, and they extend throughout the cell almost like a highway system. You might notice that cell diagrams often picture some areas of the endoplasmic reticulum with bumps, while other sections look smooth. Knowing how these different areas work is important to understanding the function of the endoplasmic reticulum as a whole.
The rough endoplasmic reticulum, or RER, gets its name from the ribosomes embedded in its surface The ribosomes that are attached to the walls of the rough endoplasmic reticulum function just like free ribosomes would. That means that they synthesize proteins , which provide the energy needed for a cell to operate.
The process of creating proteins is called translation. Some proteins are sent to the Golgi apparatus , while others are secreted into the cell exterior or kept within the membrane of the rough endoplasmic reticulum itself. There are certain proteins that are sent into the space within the rough endoplasmic reticulum. This space, which is also called the lumen , is where certain proteins are folded, modified, and assembled.
Some of these proteins will have sugar groups added to them to form glycoproteins. Likewise, some of these new proteins will be transported out of the endoplasmic reticulum, while others will stay inside the endoplasmic reticulum to perform functions there. That means that new ribosomes can detach and attach depending on the proteins the cell needs! That makes it look smooth—which is how it gets its name! How these lipids are used depends on the cell type.
Endoplasmic reticulum is a network of membranes inside a cell through which proteins and other molecules move. Proteins are assembled at organelles called ribosomes. When proteins are destined to be part of the cell membrane or exported from the cell, the ribosomes assembling them attach to the endoplasmic reticulum, giving it a rough appearance. What does the endoplasmic reticulum look like? Marta O. Jan 7, Explanation: Endoplasmic reticulum is a system of intracellular membranes that produce and transport substances.
Related questions What organelles in eukaryotic cells contain DNA? How do organelles benefit eukaryotic cells? Cells specialising in the production of proteins will tend to have a larger amount of rough ER whilst cells producing lipids fats and steroid hormones will have a greater amount of smooth ER.
Part of the ER is contiguous with the nuclear envelope. The Golgi apparatus is also closely associated with the ER and recent observations suggest that parts of the two organelles, i. This is an extensive organelle composed of greatly convoluted but flattish sealed sacs, which are contiguous with the nuclear membrane.
These are called membrane bound ribosomes and are firmly attached to the outer cytosolic side of the ER About 13 million ribosomes are present on the RER in the average liver cell. Rough ER is found throughout the cell but the density is higher near the nucleus and the Golgi apparatus. This process is called translation. Certain cells of the pancreas and digestive tract produce a high volume of protein as enzymes.
Many of the proteins are produced in quantity in the cells of the pancreas and the digestive tract and function as digestive enzymes. Proteins are produced for the plasma membrane, Golgi apparatus, secretory vesicles, plant vacuoles, lysosomes, endosomes and the endoplasmic reticulum itself. Some of the proteins are delivered into the lumen or space inside the ER whilst others are processed within the ER membrane itself.
In the lumen some proteins have sugar groups added to them to form glycoproteins.
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