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The Plant Kingdom. What is a plant?. Eukaryotic Multicellular Most are photosynthetic autotrophs Some are carnivores Some are saprophytes Aquatic and terrestrial Highly adapted and biochemically complex!. What kinds of growth forms are found in plants?. Aquatic Ground cover Herbaceous
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What is a plant? • Eukaryotic • Multicellular • Most are photosynthetic autotrophs • Some are carnivores • Some are saprophytes • Aquatic and terrestrial • Highly adapted and biochemically complex!
What kinds of growth forms are found in plants? • Aquatic • Ground cover • Herbaceous • Shrubs • Vines • Trees: midstory and canopy
Why are plants important? • Oxygen • Food • Clothing • Shelter • Medicine • Ecosystem services • Esthetic value
How are plant cells structured? • Chromosomes in a nucleus • Chloroplasts in cytoplasm • Other organelles in cytoplasm including: mitochondria, vacuoles, ribosomes, ER, Golgi bodies • Bounded by cell membrane • Outside cell membrane is cell wall
Other cell structures in plants • Stomata/stoma—openings in between plant cells in leaves for “breathing” • Guard cells—surround stomata, for opening and closing • Together these structures regulate transpiration—the process by which the water cycle flows through plant leaves
What two vital cellular processes occur in plants? • Photosynthesis—process by which light energy is chemically converted into organic compounds Carbon dioxide + water In the presence of of sunlight and chlorophyll Oxygen + Glucose
Cellular respiration • —process by which organic compounds and energy are made by all organisms Oxygen + Glucose In the presence of enzymes Carbon dioxide + water + energy (ATP)
Early plants looked very different • Some did not have distinguishable stems or leaves • Many modern plants have some similarities to ancient plants • Less complex plants have simpler structures
Stems are the most noticeable part of most plants • Stems—normally connect leaves with roots • Vascular tissue—conducting tissues in plants composed of • Xylem that has thick walled, hollow cells that carry water and minerals upward from a plant’s roots to its leaves • Phloem is made of tubes and pores that carry nutrients throughout a plant
Nonvascular and vascular plants-- • Nonvascular plants are mosses, liverworts, and hornworts • Do not need vessels because • Types of habitats-- • Division:
Nonvascular and vascular plants-- • Vascular plants have xylem and phloem, allowing them to live in many different environments other than— • Include other divisions such as--
Stems types • Herbaceous plants have soft, green stems • Woody stems have structures • Young stem has central core of pith • More mature stems have layers of xylem that form most of the wood • A cylinder of phloem is outside the xylem • Outside covered by cork
Life of wood • The layers of cork and phloem make up the bark of a tree • Wood in center is heartwood, doesn’t conduct water, gives support • Sapwood lies outside heartwood and does conduct water • Bark encloses heartwood & sapwood
Holding it all together: roots • Types: taproot and adventitious • Root hairs and root caps
What are reproductive parts of plants? • Spore • Cone • Flower • Fruit • Seed
How are plants classified? • Kingdom Plantae • Instead of being classified into PHYLA, plants are classified into DIVISIONS! • Based on structures, especially reproductive structures
Division Bryophyta app. 16,000 sp • Examples: Mosses, hornworts and liverworts • Sexual reproduction by: spores; flagellated sperm are in the antheridium and swim to the egg in the archegonium • Description: Nonvascular; small, close to the ground and to water sources; no true roots, leaves or stems; anchor with rhizoids • Habitat: close to streams in forests
Division Psilophytaapp. 10 sp • Examples: Whisk ferns • Sexual reproduction by: spores • Description: No true leaves; plant looks like mass of green stems; rare; vascular • Habitat: Tropical rainforests
Lycopodiophyta or Lycophytaapp. 15 sp. • Examples: Club mosses • Sexual reproduction by: spores • Description: scale-like leaves and stems; has true roots; vascular • Habitat: Rich woods, undisturbed areas; rare; common and tree-like 300 million years ago