Biology  5/e   Raven/Johnson
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Flowering plant life cycle: Flowers produce pollen in an anther and an egg in an ovule. The pollen is shed, is carried by wind or animal, and pollinates a flower on the stigma. The pollen extends its pollen tube down through the style into the ovary of the carpel, carrying the two sperm with it. The embryo sac, developed within the ovule, contains eight nuclei, including one egg and two polar nuclei. The egg is fertilized by one sperm while the other sperm fuses with the two polar bodies. The zygote develops into an embryo. The triploid nucleus formed by the sperm and polar nuclei grows rapigly to produce the endosperm.

Seed germination: The first prerequisite of seed germination is water penetration of the seed coat. Other environmentalk conditions must also be met, such as temperature, light type, light period, and history, i.e. such as having experienced cold.

Meristems: Apical meristem is responsible for primary growth. Secondary growth comes from lateral meristems which are of two kinds, vascular cambium and cork cambium. Vascular cambium produces secondary xylem and secondary phloem. Cork cambium forms the bark.

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