(a) Define the term 'chemotherapy'.
(b) While antacids and anti allergic drugs interfere with the function of histamines, why do these not interfere with the function of each other?

(a) Define the following terms: (i) Valency, (ii) Atomic size. (b) How do the valency and the atomic size of the elements vary while going from left to right along a period in the modern periodic table ?

A speaks truth in 75% of the cases, while B in 90% of the cases. In what percent of cases are they likely to contradict each other in stating the same fact ? Do you think that statement of B is always true ?

a] What is puberty ? b] Describe in brief the functions of the following parts in the human male reproductive system: {i) Testes (ii) Seminal vesicle (iii) Vas deferens {iv) Urethra OR Explain the significant function of each structure in human male reproductive system. c] Why are testes located outside the abdominal cavity? d] State how sperms move towards the female germ cell?

(i) Define the term functional group. Identify the functional group present in (a) H-overset(O)overset(||)(C)-H , (b) H-underset(H)underset(|)overset(H)overset(|)H-overset(OH)overset(|)(C)=O (ii) What happens when 5% alkaline KMnO_(4) solution is added drop by drop to warm ethanol taken in a test-tube ? State the role of alkaline KMnO_(4) solution in this reaction.