The two sub- units of ribosomes remain united at a critical ion level of or ribosome structure is maintained by (a) Magnesium (b) calcium (c) Copper (d) Manganese.
Option A. The two subunits of ribosomes do not remain united all the time. In fact, the two units unite only during the process of translation. Magnesium ion is essential for binding the ribosome subunits. The value is 1 to 2 millimoles for eukaryotes and 0.5 millimoles for prokaryotes. The subunits separate below this concentration. Disintegration occurs at a magnesium ion value of 0.5 millimoles in eukaryotes and below 0.3 millimoles in prokaryotes. The ribosomes form dimers when magnesium ion concentration is higher.
