BIOMOLECULES AND ENZYMES

Detailed explanation-1: -They are synthesized on the cytosolic side of the ER membrane, from water-soluble cytosolic precursors (Figure 9.17).

Detailed explanation-2: -Membrane-bound ribosomes, attached to the cytosolic side of the ER membrane, are engaged in the synthesis of proteins that are being concurrently translocated into the ER. Free ribosomes, unattached to any membrane, synthesize all other proteins encoded by the nuclear genome.

Detailed explanation-3: -Cytosolic proteins are made by free ribosomes, while proteins destined for export, or use in the membrane, are made by membrane-bound ribosomes. Proteins that remain in the cytosol are made by the ribosomes which remain freely in the cytoplasm.

Detailed explanation-4: -The nucleolus, present within the nucleus of eukaryotic cells, is responsible for the synthesis of ribosomes. Hence, it is called the site for the formation of ribosomes.