(a) Draw a diagrammatic sectional view of a mature anatropous ovule and label the following parts in it :
(i) that develops into seed coat.
(ii) that develops into an embryo after fertilization.
(iii) that develops into an endosperm in an albuminous seed.
(iv) through which the pollen tube gains entry into the embryo sac.
(v) that attaches the ovule to the placenta.
(b) Describe the characteristic features of wind pollinated flowers.

Explanation

(b) Characters of wind pollinated flowers - (i) Flowers are small usually unisexual. inconspicuous, colourless. odourless and nectarless. They are produced above the foliage (ii) In case of unisexual flowers, male flowers are more abundant. In bisexual flowers, stamens are produced in large number as compared to pistil. (iii) The anthers of wind pollinated flowers are extended and well-exposed so that the pollens are easily dispersed into wind currents. They have Large. often feathery stigma which may easily trap airborne pollen grains (iv) Pollen grains are small smooth dry and produced in large quantities. In some plants pollen are winged. (v) Non-essential parts are either absent or reduced (vi) The wind pollinated flowers often have a single ovule in each ovary and many flowers are packed into an inflorescence. Example is corn cob in which silky tassel is nothing but the stigma and style of many female flowers hanging in air to trap pollen grains