Characteristics of Plants • Eukaryotic cells • Have cell walls that contain cellulose • Cells have numerous organelles • Lack mobility • Undergo photosynthesis (autotrophic)
Evolution of Plants Onto Land To make the transition to land, plants had to adapt and undergo major modifications: • Supportive structure stems & roots • Anchoring structure roots • Transport system vascular system • Means to Reduce of Water Loss cuticle (leaf) • Means to Exchange Gases stomata (leaf) • Reproductive Structures For Dry Conditions spores, pollen, flowers, fruit, & seeds
IMPORTANCE OF PLANTS Plants are the Base of Food Chain Producers!! • Photosynthesis is the creation of food energy from sunlight, CO2, and water • This is the only source of energy for all living things! • Recall: Sunlight + CO2 + H2O C6H12O6 + O2
IMPORTANCE OF PLANTS (Con’t) • Plants Provide SHELTER • Animals use plants as protection from the elements and predators! • Plants Create the PHYSICAL ENVIRONMENT of the Ecosystem • Animals have evolved to use the habitat and conditions created by plant life to survive!
IMPORTANCE OF PLANTS (Con’t) Importance of Plants to Humans: • Food & Food Processing • Energy (Fires) • Clothing • Construction • Medicine, etc.
PLANTS & BIODIVERSITY • Plants support all the animal species living in an ecosystem • 1 plant species supports an average of 50 different animal species!! • 300 000 plant species support 15 million animal species • As many as ¼ of the world’s plant species are endangered! (Science)
Human Activity & Plants • Deforestation • Agriculture • Segmentation of Habitat • Pollution • Invasive Species (40% of all extinctions) • Monocultures