Ribosomes are a type of organelle that is found in all cell types, including both plant-like and animal-like cells, and they have one of the most important jobs.
Ribosomes are very small molecules whose function is to assist the cell in making proteins. Even under a microscope, ribosomes appear as tiny dots, floating around a cell as well as some that are attached to organelles.
In almost every place that you look in a cell, you will find ribosomes. In plant and animal cells they are attached to the organelles of the nucleus and the endoplasmic reticulum.
Even in bacteria cells you can look in the cytoplasm and see them free floating.
The origins of the ribosomes can be found in a part of the cell nucleus called the nucleolus. Ribosomes are made rRNA, a specific material that contains two parts called the “small subunit” and the “large subunit,” and each plays a role in making proteins.
Both of these subunits are made of RNA and come together when the ribosome is ready to create new proteins.
The large subunit is the location where the new protein bonds are made. In prokaryotic cells its called “50S” and in eukaryotic cells it’s called “60S.”
The small subunit is really just slightly smaller than the large subunit. Its job is to control the information flow during protein synthesis. In prokaryotic cells it’s called “50S” and in eukaryotic cells it’s called “40S.”
The “S” in the names of the subunits is for the Svedberg Unit which is a unit of measure.
Protein manufacturing in a cell is critical for its survival. Ribosomes work with a variety of other cell parts, including the nucleus, to make proteins.
They use a complicated process called “translation” for protein making, and this involves creating the protein with amino acids.
Amino acids have been compared to “small building blocks” and the ribosomes put these building blocks in the correct order so that the finished products are proteins.
Ribosomes have the ability to read and then translate the instructions so that the put the amino acid building blocks together correctly to make the mRNA protein. mRNA proteins are called the “messenger” proteins that carry the coding sequences to the cells.
There are different steps that ribosomes take in the “translation” process so that they can make proteins. If you know anything about computer programming, you will see that we use the same kind of file “start and stop” coding that the ribosomes use.
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