1. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? -Reduction of the gametophyte -Advent of the seed – replaced spore -Evolution of pollen – male gametophyte -Air dispersal instead of sperm swimming

2. Sporophyte dependent on gametophyte (mosses and other bryophytes). (a) Large sporophyte and small, independent gametophyte (ferns and other seedless vascular plants). (b) Microscopic female gametophytes (n) in ovulate cones (dependent) Sporophyte (2n), the flowering plant (independent) Microscopic male gametophytes (n) inside these parts of flowers (dependent) Microscopic male gametophytes (n) in pollen cones (dependent) Sporophyte (2n) (independent) Microscopic female gametophytes (n) inside these parts of flowers (dependent) Reduced gametophyte dependent on sporophyte (seed plants: gymnosperms and angiosperms). (c) Gametophyte (n) Gametophyte (n) Sporophyte (2n) Sporophyte (2n) Figure 30.2 Gametophyte/sporophyte relationships

3. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? -Reduction of the gametophyte -Advent of the seed – replaced spore as -Evolution of pollen – male gametophyte 2.How does an ovule become a seed? -Fertilization -Growth of the embryo

4. Figure 30.3 From ovule to seed Unfertilized ovule. In this sectional view through the ovule of a pine (a gymnosperm), a fleshy megasporangium is surrounded by a protective layer of tissue called an integument. (Angiosperms have two integuments.) (a) Fertilized ovule. A megaspore develops into a multicellular female gametophyte. The micropyle, the only opening through the integument, allows entry of a pollen grain. The pollen grain contains a male gametophyte, which develops a pollen tube that discharges sperm. (b) Gymnosperm seed. Fertilization initiates the transformation of the ovule into a seed, which consists of a sporophyte embryo, a food supply, and a protective seed coat derived from the integument. (c) Integument Spore wall Megasporangium (2n) Megaspore (n) Male gametophyte (within germinating pollen grain) (n) Female gametophyte (n) Egg nucleus (n) Discharged sperm nucleus (n) Pollen grain (n) Micropyle Seed coat (derived from integument) Food supply (female gametophyte tissue) (n) Embryo (2n) (new sporophyte)

5. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? 2.How does an ovule become a seed? 3.What’s the difference between a megaspore & a microspore? -Megasporangia  megaspores  female gametophytes (eggs) -Microsporangia  microspores  male gametophytes (sperm) -Recall seed plants are heterosporous 4.What are gymnosperms? -“naked seed” plants -Pines, spruce, fir, sequoia, yews, junipers, ginkgo -Most lumber & paper products -The gymnosperm life cycle…

6. Figure 30.6 The life cycle of a pine Ovule Key Haploid (n) Diploid (2n) Megasporocyte (2n) Integument Longitudinal section of ovulate cone Ovulate cone Pollen cone Mature sporophyte (2n) Longitudinal section of pollen cone Microsporocytes (2n) Pollen grains (n) (containing male gametophytes) Micropyle Germinating pollen grain Megasporangium MEIOSIS Sporophyll Microsporangium

7. Figure 30.6 The life cycle of a pine MEIOSIS Surviving megaspore (n) Germinating pollen grain Archegonium IntegumentEgg (n) Female gametophyte Germinating pollen grain (n) Discharged sperm nucleus (n) Pollen tube Egg nucleus (n) Ovule Key Haploid (n) Diploid (2n) Megasporocyte (2n) Integument Longitudinal section of ovulate cone Ovulate cone Pollen cone Mature sporophyte (2n) Longitudinal section of pollen cone Microsporocytes (2n) Pollen grains (n) (containing male gametophytes) Micropyle Germinating pollen grain Megasporangium MEIOSIS Sporophyll Microsporangium

8. Figure 30.6 The life cycle of a pine FERTILIZATION Seed coat (derived from parent sporophyte) (2n) Food reserves (gametophyte tissue) (n) Embryo (new sporophyte) (2n) Seeds on surface of ovulate scale Seedling MEIOSIS Surviving megaspore (n) Germinating pollen grain Archegonium IntegumentEgg (n) Female gametophyte Germinating pollen grain (n) Discharged sperm nucleus (n) Pollen tube Egg nucleus (n) Ovule Key Haploid (n) Diploid (2n) Megasporocyte (2n) Integument Longitudinal section of ovulate cone Ovulate cone Pollen cone Mature sporophyte (2n) Longitudinal section of pollen cone Microsporocytes (2n) Pollen grains (n) (containing male gametophytes) Micropyle Germinating pollen grain Megasporangium MEIOSIS Sporophyll Microsporangium

9. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? 2.How does an ovule become a seed? 3.What’s the difference between a megaspore & a microspore? 4.What are gymnosperms? -“naked seed” plants -Pines, spruce, fir, sequoia, yews, junipers, ginkgo -Most lumber & paper products -The gymnosperm life cycle… 5.What are angiosperms? - Flowering plants 6.What is a flower? - Reproductive structure of an angiosperm

10. Figure 30.7 The structure of an idealized flower Anther Filament Stigma Style Ovary Carpel Petal Receptacle Ovule Sepal Stamen Female structures Male structures

11. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? 2.How does an ovule become a seed? 3.What’s the difference between a megaspore & a microspore? 4.What are gymnosperms? 5.What are angiosperms? 6.What is a flower? -Reproductive structure of an angiosperm 7.What is a fruit? -Mature ovary -Helps seed dispersal

12. Figure 30.8 Some variations in fruit structure Ruby grapefruit, a fleshy fruit with a hard outer layer and soft inner layer of pericarp (b) Tomato, a fleshy fruit with soft outer and inner layers of pericarp (a) Nectarine, a fleshy fruit with a soft outer layer and hard inner layer (pit) of pericarp (c) Walnut, a dry fruit that remains closed at maturity (e) (d) Milkweed, a dry fruit that splits open at maturity

13. Figure 30.9 Fruit adaptations that enhance seed dispersal Wings enable maple fruits to be easily carried by the wind. (a) Seeds within berries and other edible fruits are often dispersed in animal feces. (b) The barbs of cockleburs facilitate seed dispersal by allowing the fruits to “hitchhike” on animals. (c)

14. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? 2.How does an ovule become a seed? 3.What’s the difference between a megaspore & a microspore? 4.What are gymnosperms? 5.What are angiosperms? 6.What is a flower? 7.What is a fruit? 8.The angiosperm life cycle….

15. Figure 30.10 The life cycle of an angiosperm Mature flower on sporophyte plant (2n) Key Haploid (n) Diploid (2n) Anther Ovule with megasporangium (2n) Male gametophyte (in pollen grain) Microspore (n) MEIOSIS Microsporangium Microsporocytes (2n) MEIOSIS Generative cell Tube cell Surviving megaspore (n) Ovary Megasporangium (n) Female gametophyte (embryo sac) Antipodal cells Polar nuclei Synergids Egg (n) Pollen tube Sperm (n)

16. Figure 30.10 The life cycle of an angiosperm Pollen tube Sperm Stigma Pollen grains Pollen tube Style Discharged sperm nuclei (n) Egg nucleus (n) Mature flower on sporophyte plant (2n) Key Haploid (n) Diploid (2n) Anther Ovule with megasporangium (2n) Male gametophyte (in pollen grain) Microspore (n) MEIOSIS Microsporangium Microsporocytes (2n) MEIOSIS Generative cell Tube cell Surviving megaspore (n) Ovary Megasporangium (n) Female gametophyte (embryo sac) Antipodal cells Polar nuclei Synergids Egg (n) Pollen tube Sperm (n)

17. Figure 30.10 The life cycle of an angiosperm Nucleus of developing endosperm (3n) Zygote (2n) FERTILIZATION Embryo (2n) Endosperm (food supply) (3n) Seed coat (2n) Seed Germinating seed Pollen tube Sperm Stigma Pollen grains Pollen tube Style Discharged sperm nuclei (n) Egg nucleus (n) Mature flower on sporophyte plant (2n) Key Haploid (n) Diploid (2n) Anther Ovule with megasporangium (2n) Male gametophyte (in pollen grain) Microspore (n) MEIOSIS Microsporangium Microsporocytes (2n) MEIOSIS Generative cell Tube cell Surviving megaspore (n) Ovary Megasporangium (n) Female gametophyte (embryo sac) Antipodal cells Polar nuclei Synergids Egg (n) Pollen tube Sperm (n) Double fertilization

18. Chapter 30: The Evolution of Seed Plants 1.What are the 3 most important reproductive adaptations? 2.How does an ovule become a seed? 3.What’s the difference between a megaspore & a microspore? 4.What are gymnosperms? 5.What are angiosperms? 6.What is a flower? 7.What is a fruit? 8.The angiosperm life cycle…. 9.Why is double fertilization important? -Synchronizes food development with embryo development -Prevents angiosperms from wasting nutrients on unfertilized ovules 10. What are the 2 general types of angiosperms? -Monocots -Eudicots

19. Orchid (Lemboglossum rossii) Monocot Characteristics Embryos Leaf venation Stems Root Pollen Flowers Pollen grain with one opening Root system Usually fibrous (no main root) Vascular tissue scattered Veins usually parallel One cotyledonTwo cotyledons Veins usually netlike Vascular tissue usually arranged in ring Taproot (main root) usually present Pollen grain with three openings Zucchini (Cucurbita Pepo), female (left) and male flowers Pea (Lathyrus nervosus, Lord Anson’s blue pea), a legume Dog rose (Rosa canina), a wild rose Pygmy date palm (Phoenix roebelenii) Lily (Lilium “Enchant- ment”) Barley (Hordeum vulgare), a grass Anther Stigma California poppy (Eschscholzia californica) Pyrenean oak (Quercus pyrenaica) Floral organs usually in multiples of three Floral organs usually in multiples of four or five Filament Ovary Eudicot Characteristics MONOCOTS EUDICOTS