1. Review of reproductive biology 2. Pollination Ecology On the Function of Flowers -precise placement -outcrossing -variation in flowers -life cycle

Figure 38.2 Review of an idealized flower

Figure 38.3a Trillium

1. Review of reproductive biology 2. Pollination Ecology On the Function of Flowers -precise placement -outcrossing -variation in flowers -life cycle

Figure 38.1 Simplified overview of angiosperm life cycle

Figure 38.3ax2 Lily

Figure 38.4 The development of angiosperm gametophytes (pollen and embryo sacs)

Dispersed Pollen Grain Generative Cell Tube Cell Pollen Coat 4 Microspores

Figure 38.5 Pollen grains have tough, ornate, and distinctive walls

Figure 38.3ax1 Lily

Cross Section of an Ovary One ovule just after meiosis

Figure 38.4 The development of angiosperm gametophytes (pollen and embryo sacs)

Mature female gametophyte Egg Four-nuclear female gametophyte after two mitotic divisions of the megaspore)

Figure 38.9 Growth of the pollen tube and double fertilization

Figure The development of a dicot plant embryo

Figure The life cycle of an angiosperm

1. Review of reproductive biology 2. Pollination Ecology On the Function of Flowers -precise placement -outcrossing -life cycle -variation in flowers

Angraecum (Orchidaceae)

1. Review of reproductive biology 2. Pollination Ecology On the Function of Flowers -precise placement -outcrossing -life cycle -variation in flowers

Three paths for pollen flow: selfing: 1. Within flower 2. Between flowers 3. outcrossing (between plants)

Red Maple Flowers staminate pistillate

Figure 38.3e Maize, a monoecious species

syndromes

Foxgloves and outcrossing

Figure 38.3bx1 Foxglove

Female zone Male zone Bees fly up Then start over at the bottom Three components to outcrossing in foxglove 1. Young flowers are male, old are female 2. Young flowers are nearer the top 3. Bees fly up.