Answer the following problems.

problem1) Make a diagrammatic sketch of a mature anther as seen in transverse section. prepare the characteristic features of the cells that constitute a fully developed anther.

problem2) What is the direction of flow of nutrients in an ovule? Which tissues are involved in flow of nutrients? Use a diagram to clarify your answer.

problem3) Describe the finer details of the events that follow the release of the contents of the pollen tube in the embryo sac.

problem4) Differentiate between simple and multiple polyembryony. Mention the names of the sexual and asexual tissues/structures that give rise to polyembryos and prepare the ploidy levels of these embryos.

problem5) Using clear and labelled diagrams highlight the histological changes that occur in the ovule of Gossypium spp. during the development of its seed coat, fuzz and lint hairs.

problem6) Prepare an account on floral development in plants including these aspects: conditions required by plants for floral initiation, morphological changes accompanying floral induction, and the prominent molecular events that follow floral induction.

problem7) Elaborate the ensuing aspects of scenescence in plants: different ways of scenescence, Richmond & Long effect, roles of light-dark periods and plant growth regulators.

problem8) Give any two applications of apical dominance in plants.

problem9) prepare the source, origin, properties and uses of commercial cork. The cork is cut in which plane for use as bottle-cork and why?

problem10) ‘The phenomenon of embryogenesis is not necessarily confined to the reproductive cycle’. Justify the statement.

problem11) Citing any two exs describe the structure of micropylar and chalazal haustoria of endosperm. Mention the names of the structures where these haustoria extend. Make labelled diagrams of the two exs discussed.

problem12) Where is the male germ unit organized? What are its components? Mention their roles. Name the techniques that helped us in knowing their finer details.