Give a brief account of viruses with respect to their structure and nature of genetic material. Also name four common viral diseases.

Name any two viruses whose genetic material is RNA.

Give reason a. Drosophila is the ideal material for genetic study. b. Haemophilia is more common in males. c. Aneuploidy leads to variation. d. Sex of the child is determined by father.

Discontinuous variation is also called quantitative inheritance. Continuous variation is also called qualitative inheritance. Variation is the raw material for evolution. Variation provides genetic material for natural selection.

Atom of seven elements A,B ,C, D, E,F and G have a different number of electronic shells but have the same number of electrons in their outermost shells. The element A and C combine with chlorine to form an acid and common salt respectively. The oxide of element A is liquid at room temperature and is a neutral substance while the oxides of the remaining six elements are basic in nature . Based on the above information, anwer the following question given ahead : Show the formation of the compound by a combination of element C with chlorine with the help of electronic structure .

Read the given statements that describe certain infectious particle. (i) It was discovered T.O. Diener and was found to be smaller than viruses. (ii) It causes potato spindle tuber disease. (iii) It is a free RNA particle which lacks the protein coat. (iv) It has low molecular weight RNA as genetic material. Which of the following is referred to here?

Genetic modification of organisms can have unpredictable results when such rganisms are introduced into the ecosystem. Is there any regulatory authority in India to, monitor such development of GM crops? Give a brief account.

Write the main structural difference between RNA and DNA of the four bases, name those which are common to both RNA and DNA.