In grasses what happens in microspore mother cell for the formation of mature pollen grains:
1.  One meiotic and two mitotic divisions
2.  One meiotic & one mitotic division
3.  One meiotic division
4.  One mitotic division

In Angiosperm all four microspores of a tetrad are covered by a layer that is formed by:

1. Pectocellulose

2. Callose

3. Cellulose

4. Sporopollenin

In a flowering plant, archesporium gives rise to:

1. Only the wall of the sporangium

2. Both wall and the sporogenous cells

3. Wall and the tapetum

4. Only tapetum and sporogenous cells