Ribosomes

• Most genes contain information to make proteins.
• Ribosome is a very small structure found in all lining cells that plays a crucial role in protein synthesis.
• Ribosome consists of two main submits, comprised of RNAS proteins, which reads genetic codes and assemble amino acids into polypeptide chains.
• Large submit in ribosome catalyses the formation of peptide bands between amino acids to form a polypeptide chain.
• Ribosome is highly ordered with the RNA molecules forming a scaffold that positions the proteins in the correct orientation to carry out their functions.
• Ribosome is an intercellular structure made of RNA protein and is the site of protein synthesis in cell.
• Ribosome reads the mRNA Sequences, translates that genetic code into a specified string of go amino acids, and grows these into long chains that fold to form a protein.
• Ribosome is a conveyor belt process where ribosome synthesises proteins in a rapid, continuous, and coordinated manner.
• Ribosome consists of 30s small subunit and 50S large subunit.
• Ribosome is a complete ribosome.
• Most proteins require molecular Chaperones to fold properly.
• Many Chaperones are Heat-shock proteins (HSP), which are synthesised in increased amounts when cells are exposed to higher temperatures but are constitutively expressed.
• A useful protein needs to have a 3D conformation, bind to Co-factors and any other modifications.
• Several major families of Heat-shock proteins (HSP) function in different organelles.
• During folding, hydrophobic residues in the interior of the protein care.
• The structure of ER consists of a central hollow cylinder containing a protein ring to which target proteins are threaded for degradation.
• Chaperones ensure the correct pathway is followed.
• Non-covalent bonding occurs between ports of the molecule.
• ER detects protein, retrotranslocates to cytosol for destruction.
• Some proteins fold in the exit tunnel of the ribosome.
• The major part of protein folding occurs as the protein emerges from the ribosome exit tunnel.
• Ribosome is a site where protein synthesis occurs.
• Ribosome consists of ribozymes or catalytic RNA, which direct the catalytic steps of protein synthesis.
• Testosterone is synthesized from Cholestrol in the cytoplasm of the Leydig cells of the testis.
• Cellular adaptation is to expand the SER membrane to enable cells to carry out their expected functions.
• Scramblase is a phospholipid translocator which causes the two leaflets to equilibrate.
• Lipophilic drugs are modified to increase water solubility in hepatocytes of liver.
• In some cells, the endoplasmic reticulum has specialized roles.
• Hepatocytes are the major producers of lipoproteins.
• The endoplasmic reticulum is a major site of phospholipid synthesis.
• Steroid hormones are synthesized on the stroma.
• Cholesterol is a precursor to steroid hormones.
• New phospholipids are assembled in the outer half of the ER membrane by enzymes which combine their components.
• The endoplasmic reticulum has no ribosomes in most cells but is transitional between the Golgi and is sparse of all membrane.
• Protein may be released into the filtrate or integrated into the membrane.
• The sarcolemmal reticulum is a uninuclear organelle that acts as a reservoir in muscles but also as a site of membrane synthesis.
• New phospholipids are carried to the Golgi, plasma membrane, lysosomes & endosomes by vesicular transport.
• Ribosome consists of ribozymes or catalytic RNA, which synthesise more protein in an active cell.
• Ribosome consists of ribozymes or catalytic RNA, which maintain correct reading to ensure accuracy.
• Small Submit Scans MRNA for AUG Codon and binds to tRNA-met, then recruits the large submit.