structures. Pollen sticks at stigma. Andro = male. Gyno = female. Eclum = house. Petal attracts pollinators (modified leaf). Sepal is sometimes attractive. Angiosperm reproduction: Sporophyte. Gametophytes. Embryo sac is another name for the female gametophyte. Pollination: Pollination types - Wind and animals. Requires effort. Primitive. Pollinator attraction: Smell – flies. Sweet odor – most insects. Flower color – white, yellow, red, purple. Flower pattern – UV reflection. Flower shape and/or scent – sex surrogate tricket. Fertilization: Double fertilization – Sperm with 2 polar nuclei = 3n = endosperm. Sperm with egg = embryo = 2n. What are fruits? In angiosperms, the ovary wall. The entire vessel is the Fruit. Angiosperm means vessel seed. Fruits take on many shapes and forms to help disperse the seeds inside them. Early growth and Timing: There are practically as many forms of fruits and seed dis as you can imagine. Most fruits remain hard, sour, green, or closed until they ripen. Seed dispersal: Unassisted – Ruppia maritma. The seeds float away in water currents. Wind – seeds often attached to modified structures. Cling adapted: seed or fruits cling. Animals. Why green fruit? Green is difficult for predators to see. Tough. Sour. Seeds still undeveloped. Why red fruit? Red is easy for carriers to see, difficult for insects to see. Insects see blue light better than red light). Seeds are developed. Of and sweet to carrier. Eaten and seeds defected elsewhere. Animals: Sactterhoarded -stored by mammals. Seeds are typically large in size. Water – tend to be large and well protected. Humans.
Plant life spans.: Annuals – Senescance ages and dies at the end of one growing season. Flowers and fruits to produce next generation. Biennials – two years to complete lifecycle. In the first year, plant grows vegetation structures. Then it enters a period of dormancy. Releases seed then dies. Perennials. Lives for many years. Usually dies back at the end of a growing season, but stems and below ground roots stay alive.