Endoplasmic reticulum (ER) is another long scientific name for an organelle with the main job of transportation. The ER moves chemical compounds back and forth from the nucleus.
Only cells that have a nucleus also have an ER. This means that animal and plant cells all have ER’s but simple cells such as bacteria don’t have ER’s because their cells lack a nucleus.
Think of the endoplasmic reticulum like a series of very tiny roads, only in the case of the ER, they are actually tubes.
The clear ER tubes travel everywhere in the cell parts. There are some ER that travel to various organelles and others that go to and from the nuclear membrane to the cellular membrane outside.
Wherever the ER goes, it carries various materials to the location where they are needed.
The function of the ER is so vast that it is divided into two parts that are connected: The rough endoplasmic reticulum (rough ER) and the smooth endoplasmic reticulum (smooth ER). Each part has a separate role in supporting the nucleus but they also work closely together so that the cell is healthy.
The smooth ER is mainly a storage area and is made of a network of tubes that work closely together. The smooth surface gives it its name.
It stores steroids and fatty acids and will release them when the cells require them. Another portion of its job includes the ability to break down lipids and carbohydrates into simple molecules.
Once done, it can move them to other parts of the cell. It is responsible for the production of steroids and proteins, maintaining the plasma membranes and all of the pathways so that the molecules move around easily.
The rough ER get its name because it is covered with ribosomes which makes it have a bumpy appearance. The rough ER is really made of many sacs that are flattened.
The main job of the rough ER is in transporting molecules back and forth from the nucleus but it also is responsible for creating and packaging proteins that are sent throughout the cells by vesicles, using the golgi apparatus Other organelles are responsible when additional packaging and distribution is required.
Ribosomes are rather unusual in that while they are a type of organelle in the cell, they also have the ability to attach themselves to other organelles.
This is what happens with rough ER’s. It’s the ribosomes that actually create proteins and they accomplish this through the creation of long chains of amino acids that they have pieced together.
Once the proteins are made, they are moved into the rough ER in the same way that you would board a train. From that point, the rough ER travels and distributes the proteins to other parts of the cell.
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