What are Ribosomes???
* Granular structures, first observed by George Palade under an electron microscope
* Composition: RNA and proteins
* Not surrounded by any membrane
* Prokaryotic cells have ribosomes 70SE. Eukaryotic ribosomes are 80S. S stands for Svedberg unit, and is indicative of density and size.
Ribosome plays a very important role in prtoein synthesis.
It is a cell organelle which has no membrane which do protien synthesis and is usually attached to the Endoplasmic Reticulum or freely moving in cytoplasm.
1.It is produced by the nucleolus inside the nucleus.
2.It is the only cell organelle present in both eukayotic and prokaryotic cell.