Ribosome
What is a ribosome?
A ribosome is a molecule of macro dimensions that is responsible for the synthesis or translation of the amino acids of mRNA (in eukaryotic cells) and the manufacture of proteins in living beings (in eukaryotic and prokaryotic cells).
The most significant function of the ribosome is the synthesis of proteins, an essential element for the ordinary functioning of all living beings. In prokaryotic cells (without a defined nucleus), ribosomes are derived in the cytoplasm, while in eukaryotic cells (with a defined nucleus) they are created in the nucleolus within the cell nucleus.
In the case of ribosomes in prokaryotic cells, the ribosome returns information from the messenger RNA (mRNA or mRNA) directly and immediately. In contrast, in eukaryotic cells, the mRNA must traverse the nuclear envelope through the nuclear pores to the cytoplasm or rough endoplasmic reticulum (RER) to reach the ribosomes.
In this way, in animal and plant cells (eukaryotic cells), this specimen of ribosome converts the information contained in the mRNA and when combined with the correct ribosome in the cytosol, it will extract the protein with the specific sequence of amino acids. This process is called protein translation or synthesis.
Characteristics
- They are present in most of the cells that make up living beings.
- They are responsible for translating the information that is required to be able to carry out an effective protein production.
- Protein is the basis of the necessary biological processes within the life cycle of the cell.
- Its main purpose is the production of protein according to the information transmitted by the amino acids encoded in the messenger RNA (mRNA or mRNA).
Composition
Ribosomes are made up of two subunits , one of proportional size and a smaller one, passing between them is a nucleic acid chain that is compressed. Each ribosome subunit is made up of a ribosomal RNA and a protein. Together they organize the translation and catalyze the reaction to generate polypeptide chains that will be the basis for proteins.
In the same vein, transfer RNAs (tRNAs) are responsible for bringing amino acids to the ribosome and pairing the messenger RNA with the amino acids that encode the protein that will be produced by the ribosome.
Function
The function of ribosomes is the synthesis of proteins through the use of genetic data that they receive from messenger RNA (mRNA). The mRNA, in short, is ribonucleic acid that houses the genetic code that comes from the nucleus of the cell. In this way, it defines how the amino acids of proteins should join, functioning as a kind of pattern or model for synthesis.
The genetic process that ribosomes develop is known as translation. In it, the ribosome is responsible for translating the mRNA and then assembling the amino acids provided by the transfer RNA to the protein.
Scientists have distinguished twenty amino acids. Each one is encoded in the genetic code by one or more codons: in total, 64 codons are known. Codons are nucleotide triplets and ribosomes, in their translation process, work with these elements.
Examples of ribosomes
- Prokaryotic ribosome .
- Eukaryotic ribosome .
- Mitochondrial ribosome .
- Plastid ribosome.