For two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below: a. Both A and R are true, and R is correct explanation of the assertion. b. Both A and R are true, but R is not the correct explanation of the assertion. c. A is true but R is false. d. A is false but R is true. Assertion: ln grasshoppers, females are hetero gametic and males are homo gametic. Reason: ln grasshoppers, male has only one sex chromosome (XO) whereas the female has sex chromosomes (XX).

What is reproduction? What are the two types? Which one of the two confers new characteristics on the offspring and how?

Updated 1/20/2026

In terms of evolution, what is the significance of homology between a human hand and a wing of a bird?

Updated 1/20/2026

“The maximum concentration of harmful chemicals accumulates in human beings?” State the phenomenon involved and justify this statement.

Updated 1/20/2026

What is ozone? How does it protect the organisms on the earth?

Updated 1/20/2026

(a) In human body what is the role of • seminal vesicles and • prostate gland. (b) List two functions performed by testes in human beings.

Updated 1/20/2026