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  • Biology 1B - Lecture 32: Angiosperm life cycle and diversity General Biology
  • Pollination And Fertilisation Check us out at Pollination : Structures the diagram shows. Include the stigma, style, ovary, ovule and embryo sac (female gametophyte). Draw a line out from each structure and then print the correct label at the end of each line. Notice again that the ovule of the flowering plant is completely enclosed within the carpel. This is an important evolutionary advancement over the gymnosperms (pine) where the ovule is exposed on the ovulate cone scale surface. Next use an orange colored pencil to shade in the megagametophyte (embryo sac). The color will help you remember the megagametophyte is the haploid (1N) stage of the plant. Everything else shown in the diagram is part of the sporophyte stage of the plant . The cells of sporophyte tissue always have diploid chromosome numbers (2N). Finally, the diagram illustrates how well the megagametophyte is protected by the surrounding tissue of the sporophyte plant.Pollination occurs when pollen grains are transferred from the anther of one flower to the stigma of the same flower or to another flower's stigma of the same species. The transfer agent is wind in some species and insects, birds and bats in others. Successful pollination requires simultaneous maturation of the stamens and carpels. Show pollination by drawing two pollen grains on the stigma of your diagram. Color the pollen grains orange to show they are haploid and microgametophytes. Draw a pollen tube extending from one pollen grain down into the ...