Welcome to the Channel Biotech and Science. Let's talk about ribosomes, definition. Ribosomes are cellular structures responsible for protein synthesis, functioning as the machinery that translates genetic instructions from RNA into proteins. These tiny organelles, found either floating freely in the cytoplasm or attached to the endoplasmic reticulum, consist of two subunits small and large that come together during protein synthesis. Key points about ribosomes 1. Protein synthesis They read messenger RNA, mRNA, transcripts, and translate the genetic code carried by mRNA into specific sequences of amino acids, forming proteins. 2. Two subunits Ribosomes are composed of a small and a large subunit, each with their specific roles, during translation. The small subunit reads the mRNA, while the large subunit joins amino acids to form a polypeptide chain. 3. Location They can be found in two main cellular locations, free floating in the cytoplasm or attached to the rough endoplasmic reticulum, ER. Ribosomes attached to the endoplasmic reticulum are involved in synthesizing proteins that are either secreted from the cell or incorporated into the cell membrane. 4. Conservation of structure Despite variations in cells, the basic structure and function of ribosomes are highly conserved across species, showcasing their fundamental role in life processes. 5. Ribosomal RNA RNA Alongside proteins, ribosomes contain RNA, which plays a critical role in catalyzing the formation of peptide bonds between amino acids during protein synthesis, 7 ribosome composition. Ribosomes are made up of two major components, ribosomal RNA, RNA, and proteins. The small and large subunits consist of a combination of ribosomal RNA molecules and various ribosomal proteins. 8. Assembly Ribosomes are assembled in the nucleolus, a distinct region, within the cell's nucleus. The assembly involves the synthesis of RNA, which combines with ribosomal proteins, to form the small and large subunits. 9. Three stages of translation Translation, the process carried out by ribosomes, occurs in three main stages, initiation, elongation, and termination. Each stage involves specific interactions between mRNA, transfer RNA, TRNA, ribosomal subunits, and amino acids, to build the protein chain. 10. Types of ribosomes Eukaryotic cells possess cytoplasmic ribosomes for protein synthesis within the cell, and also have ribosomes associated with the rough endoplasmic reticulum, RER, involved in synthesizing proteins for secretion or membrane bound proteins. Synthesis The number and activity of ribosomes in a cell can be regulated based on the cells needs for protein synthesis, adjusting to changing environmental conditions, or developmental stages. Thanks for watching. Don't forget to like, share, and subscribe.