2. Plant Genealogy and Taxonomy Notes Know underlined terms

3. I. NON-VASCULAR PLANTS: Algae, mosses First to evolve on earth (about 470 million years ago). No special vessel-like system for transmission of fluids.

4. II. VASCULAR PLANTS: Special vessel-like system for transmission of fluids: A. Non-Seed Bearing (spores): EX: Ferns Evolved about 400 mya. A plant’s “circulatory system”

5. II. VASCULAR PLANTS: B. Seed-bearing: 1. Gymnosperms “naked-seed” (no fruit). Evolved ˜ 360 mya: male/ female parts; disperse, collect pollen; form seeds EX: Conifers (pines, redwoods, etc.)

6. II. VASCULAR PLANTS: B. Seed-bearing: 2. Angiosperms “covered seeds”; flowering plants (fruit). Evolved ˜180 mya. male/ female parts in flower; disperse, collect pollen; form fruits and seeds

7. II. VASCULAR PLANTS: 2. Angiosperms: a. Monocots (1 cotyledon [1 seed lobe], parallel leaf veins): EX: Grasses, corn Where seed stores food --like an egg’s yolk.

8. II. VASCULAR PLANTS: 2. Angiosperms: b. Dicots (2 cotyledons [2 seed lobes], networked leaf veins): EX: most other spp.

9. II. VASCULAR PLANTS: 3. Other descriptions of vascular plants (may be gymnosperms or angiosperms, monocots or dicots): Annuals: Plants that complete their lifecycle in a year or less (go to seed every year) Perennials: Plant that lives for more than 2 years.

10. III. PLANT EVOLUTION Consider the power and role of evolution in plant genealogy: A. Background: What is evolution? Cumulative changes in a population as a result of: 1. appearance of variation in a population (often caused by mutation), 2. a selective force that selects for or against the survival of certain individuals in the population 3. reproduction: passing on of the selected characteristic that allowed for survival.

11. III. PLANT EVOLUTION B. Where did flowers come from (what is the source of variation in the plant population)? Modified/ adapted leaf structures. C. Why were flowers selected? Sexual reproduction increases variation--vital to evolutionary process. Flowers are a means of sexual reproduction.