Ribosomes in eukaryotes and prokaryotes

A ribosome is a highly complicated structure that is made up of reran (ribosomal RNA) along with different small proteins. It is found in huge numbers in all prokaryotic as well as eukaryotic. Prokaryotic and eukaryotic ribosomes are slightly different from each other structurally. For prokaryotic animals, ribosomes are almost 60% ribosomal RNA and 40% different proteins. In eukaryotic animals, the amount of both ribosomal RNA and protein is about 50% each.  The term ribosome is made up of two words, rib means ribonucleic acid and soma means body. 

What are Ribosomes?

Ribosomes are intricate molecular machines that are found in all the living things of the earth.  It produces proteins with the help of different amino acids. The synthesis of protein is called translation. Protein synthesis is the principal function that is executed by all living animals. It is specialized organelles of the cells and it is easily found in both eukaryotic and prokaryotic cells. Every organism needs ribosomes for the synthesis of proteins. Protein is essential for every living thing to sustain their lives. 

Structure of Ribosome

A ribosome is made up of rRNA and different protein molecules. Since RNA is a part of ribosomes that is why it is also called a ribonucleoprotein. The ribosome consists of two subunits, one large subunit, and one small subunit. In the small subunit of ribosome, the mRNA binds and gets decoded and on the other hand, the larger subunit binds with amino acids. The smaller and larger subunits of ribosomes get attached by interaction among rRNA in one of the subunits and protein in the other subunit.  It is widely found in the cytosol of animal cells and plant cells. 

Composition of Ribosome

“Composition of ribosomes” contains protein and RNA. Inside the E.coli, a prokaryotic animal, it contains 66% of RNA and 34% of protein. On the other hand, In eukaryotes, it consists of 60% RNA and 40% RNA. The chemical composition of two different units is different from each other. In the prokaryotic animals, the proteins in the smaller unit that is 30S are indicated as S1, S2, and so forth. The proteins in the larger subunit (the 50S) of the ribosomes are classified as L1, L2, and so forth. The sedimentation coefficient and size of ribosomes and their two subunits and the ribosomal RNA vary in eukaryotic and prokaryotic cytoplasm, chloroplast.  

Eukaryotic Ribosomes

“Eukaryotic ribosomes” are different from that of prokaryotic. In “eukaryotic ribosomes” the smaller subunit (the 40s) has 33 proteins and just 1 rRNA. The larger subunit, the 60s has 3 rRNA molecules. Out of three, two are almost similar to that of prokaryotes. All the subunits of ribosomes have a similar function to prokaryotic ribosomes. The RNA precursor or pre-RNA in eukaryotic ribosomes are particularly conserved with 5.8s, 18s, and 28s rRNA that are encoded inside a transcript. This transcript is produced by “RNA polymerase I”.  It has the order of   5’ to 3’.  

Prokaryotic Ribosomes

“Prokaryotic ribosomes” are composed of the 70S (S= Units of Svedberg) ribosomes. “Prokaryotic ribosomes” have a key role in the synthesis of protein, which is a highly demanding substance for the maintenance of all living animals. The 70S ribosome is composed of 30S and 50S subunits. The 30S is the smaller subunit and the 50S is the larger subunit of the ribosome. The smaller subunit contains 16S ribosomal RNA (rRNA). On the other hand, the larger subunit of the ribosome contains 5S rRNA and 23rRNA. The smaller subunit of “prokaryotic ribosomes” is the target place of antibiotics (gentamicin and tetracycline). The smaller subunit has a part in the “mRNA translation”. 

Ribosomes in Eukaryotes and prokaryotes

The principal dissimilarity between “ribosomes in eukaryotes and prokaryotes” is that eukaryotic ribosomes (the 80S) are generally larger, while the prokaryotic ribosomes (70S) are smaller in size. In addition to that, ribosomes of prokaryotic cells are scattered in the cytoplasm. On the other hand, eukaryotic ribosomes of eukaryotic cells are attached to the outside membrane of ER (Endoplasmic reticulum) and nucleus. “Ribosomes in eukaryotes and prokaryotes” are a type of cellular machine that helps in the translation of mRNA (Messenger RNA) into a sequence of amino acids. Both the prokaryotic and eukaryotic ribosomes are composed of two different subunits (larger and smaller). Every subunit consists of ribosomal protein and rRNA (Ribosomal RNA). 

What is the function of prokaryotic and eukaryotic Ribosomes? 100

The objective of both eukaryotic and prokaryotic ribosomes is to produce proteins. The ribosomes translate mRNA into proteins with the assistance of tRNA (Transfer RNA). Proteins are essential for the different functions of cells. Protein synthesis is the primary function of ribosomes. At a time, each codon of mRNA molecule is read by the ribosomes during the synthesis of proteins. The reading of every codon ends in the establishment of a long chain of proteins. 

Conclusion

“Ribosomes in eukaryotes and prokaryotes” is a vital chapter in “molecular biology”. For the understanding of ribosomes, one has to deeply study the chapter. In this study, the overview of ribosomes is discussed with their types, structure, and functions. Here the differences between the prokaryotic and eukaryotic ribosomes are discussed with the assistance of their chemical compositions, structure, and many more.