CURRENT AFFAIRS

Detailed explanation-1: -Viral Structure. In the simpler viruses the virion consists of a single molecule of nucleic acid surrounded by a protein coat, the capsid; the capsid and its enclosed nucleic acid together constitute the nucleocapsid. In some of the more complex viruses the capsid surrounds a protein core (Fig.

Detailed explanation-2: -The first knowledge of virus structure was a result of Stanley’s studies of tobacco mosaic virus (TMV) and the subsequent X-ray fiber diffraction analysis by Bernal and Fankuchen in the 1930s.

Detailed explanation-3: -The first significant development in structural virology was in 1935, when Stanley crystallized the infectious particles of tobacco mosaic virus (TMV) (Stanley, 1935) and subsequently Bawden and Pirie crystallized tomato bushy stunt virus (TBSV) (Bawden and Pirie, 1938).

Detailed explanation-4: -The single-stranded RNA genomes of COVID-19 encode two large genes, the ORF1a and ORF1b genes, which encode 16 non-structural proteins (nsp1–nsp16). The structural genes encode the structural proteins, spike (S), envelope (E), membrane (M), and nucleocapsid (N). The accessory genes denoted in shades of green.