Which of the follow ing protein is synthesized in free ribosome -
Cytosolic proteins
Secretery proteins
Membrane proteins
None
Ans. is 'a* i.e., Cytosolic proteinsRibosomeso Ribosomes are the actual sites of protein synthesisQ. The ribosomes are small granules of RNAs. Ribosomes are usually occur in clusters called polyribosomes attached to one mRNA molecule, an arrangement that increases the rate of polypeptide synthesis. There are two types of polyribosomes : -Free (cytosolic) : - Present free in cytosol.Bound polyribosome : - Present on rough ER.o Both tvpes can synthesize protein : -Proteins synthesized by polyribosomesCytosolic (free) PolyribosomesBound (rough ER) Polyribosomeso Cytosolic proteins, e.g.. Hemoglobino Cytoskeletal proteinso Mitochondrial proteinso Nuclear proteinso Peroxisomal proteinso Synthesize all membrane proteinsMitochondrial membraneER membraneGolgi apparatus membranePlasma membraneo Secretory proteinso Lysosomal enzymes
Molecular Genetics