Biology  5/e   Raven/Johnson
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Turgor pressure: Most plants are hypertonic with respect to their environment. The resulting osmotic pressure that presses the cell membrane against the rigid cell wall is referred to as turgor pressure.

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 rapidly to produce the endosperm.

Apical meristems: Apical meristem forms three kinds of primary meristem. The three primary meristems and their maturation products are protoderm, which produces epidermis; procambium, which produces primary vascular tissue, and ground meristem, which produces ground tissue.

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

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