Distinguish between unisexual and bisexual flowers giving one example of each. Draw a diagram showing the process of germination of pollen grains on stigma and label the following parts:

(i) Female germ cell

(ii) Male germ cell

(iii) Ovary

List the new Cartesian sign convention for reflection of light by spherical mirrors. Apply these conventions for calculating the focal length and nature of a spherical mirror which forms a 1/3 times magnified virtual image of an object placed 18 cm in front of it.

What are hydrocarbons? Write the name and general formula of (i) saturated hydro � carbons, (ii) unsaturated hydrocarbons, and draw the structure of one hydrocarbon of each type. How can an unsaturated hydrocarbon be made saturated?

Or

What are detergents chemically? List two merits and two demerits of using detergents for cleansing. State the reason for the suitability of detergents for washing, even in the case of water having calcium and magnesium ions.

Draw a diagram of human female reproductive system and label the part

(i) that produces eggs.

(ii) where fusion of egg and sperm takes place.

(iii) where zygote is implanted.

What happens to human egg when it is not fertilized?

The aqueous 'solutions of copper 'sulphate and zinc sulphate appear