1. Chapter 38 Angiosperm Reproduction and Biotechnology

2. Angiosperms Anthophyta More specialized xylem evolved. Tracheids seen in gymnosperms gave rise to vessel elements Xylem is reinforced by second cell wall, the fiber (also seen in conifers) Xylem is reinforced by second cell wall, the fiber (also seen in conifers) Flower is the reproductive structure Coevolution is seen between flowers and animals

3. Sporophyte/Gametophytes The life cycle of the angiosperms shows very reduced gametophyte generations. What is the male gametophyte? What is the female gametophyte? What is pollination? Bringing pollen to the stigma. How does self-incompatibility work? Ability of a plant to reject its own pollen and sometimes the pollen of closely related individuals

4. Double Fertilization The pollen tube grows following pollination and leads to double fertilization. What is fertilized? Sperm + egg = zygote (2n) Sperm + 2 polar nuclei = endosperm (3n)

6. Seed Development Endosperm develops before embryo Endosperm provides food for developing embryo Embryo reaches a certain size and then enters dormancy until germination.

7. Development of a eudicot embryo

10. Germination How can seed dormancy be advantageous to a plant? Helps with dispersal Doesn’t leave dormancy until conditions are good What are some conditions for breaking dormancy? 1. Desert – Only after good rainfall 2. Chaparral – fire 3. Others – coats weakened by digestive enzymes as they pass through animal’s digestive tract

11. Germination depends upon…. Imbibition-uptake of water due to the low water potential of the dry seed Hormone release

13. Radicle emerges from seed Shoot tip breaks through the soil. Until this point how has the embryo received nutrients? Endosperm(food)and radicle (water).

15. The Fruit What is a fruit? After fertilization the ovary becomes the fruit. It protects the seeds. Name three modifications that different fruits have for seed dispersal. 1. Sweeten and turns colorful when ripe 2. Have burrs that can stick to animal’s fur 3. Feathery like dandelions for wind dispersal of seeds

18. Review the Evolution of Alternation of Generations in Plants