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Kinds of Plants. I. Non-Vascular Plants. A. Survival of Non-Vascular Plants 1. need to have moisture 2. no vascular system for transporting water and nutrients 3. lack true roots, leaves, and stems but have structures that resemble them. B. Key Features of Non-Vascular Plants
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A. Survival of Non-Vascular Plants • 1. need to have moisture • 2. no vascular system for transporting water and nutrients • 3. lack true roots, leaves, and stems but have structures that resemble them
B. Key Features of Non-Vascular Plants • 1. Small size- transport water and nutrients through osmosis and diffusion, only a short distance • 2. Larger gametophyte- Rhizoids (hair-like projections) anchor the gametophyte to the surface they grow on, sporophytes grow on the gametophytes and depend on them for nutrients • 3. Require water for sexual reproduction- eggs and sperm form in separate structures or separate plants and the sperm must use water to get to the eggs to fertilize them
C. Kinds of Nonvascular Plants • 1. Mosses- Bryophyta • A. Leafy parts are gametophytes • B. cuticle, stomata, and simple conducting cells • C. sporophyte grows on the tip of the gametophyte and has a spore capsule
2. Liverworts- Hepatophyta • A. grow in mats of many individuals • B. No conducting cells, cuticles, or stomata • C. Liverworts have flattened lobes • D. Sporophytes grow on top gametophytes
3. Hornworts- Anthocerophyta • A. completely lack conducting cells • B. Sporophyte has a stomata and a cuticle • C. Gametophyte is flattened and sporophyte grows upward from gametophyte
A. Characteristics • 1. do not produce seeds • 2. underground horizontal stems called rhizomes • B. Key Features of Seedless Vascular Plants • 1. Vascular system- contain xylem and phloem reinforced with lignin (a major part of wood), and develop true roots, stems and leaves • 2. Larger sporophyte- easier for wind to carry away spores, water is needed for fertilization • 3. Drought resistant spores- thickened walls of spores resist drying
C. Kinds of Seedless Vascular Plants • 1. Ferns- Pterophyta • A. most abundant in the tropics • B. sporophytes are what you see and they have rhizomes anchored by roots and leaves called fronds • C. young leaves are called fiddleheads • D. spores grow in clumps on the lower sides of fronds
2. Club Moss- Lycophyta • A. unlike true mosses- have roots, stems and leaves • B. Stems develop from underground rhizomes • C. Specialized leaves • D. Clusters of spore bearing leaves make a cone
3. Horsetails- Sphenophyta • A. roots, stems and leaves • B. vertical stems grow from rhizomes and have joints where whorls grow • C. cones form at the ends of stems
4. Whisk Ferns- Psilotophyta • A. highly branched stems, no leaves or roots • B. Produce spores at the tips of short branches
A. Seed plants whose seeds do not develop within a sealed container (fruit) • B. means “naked seed” • C. Key Features of Gymnosperms • 1. Seeds- protect the plants embryo and provide it with nutrients and permit them to survive in unfavorable conditions • 2. Greatly Reduced Gametophyte- tiny male and female gametophytes that form within tissues of sporophyte • A. Male- pollen grains • B. Female- form structures that become seeds • C. both develop in cones • 3. Wind Pollination- sperm in pollen are carried to the egg by drifting in the wind making sexual reproduction possible even in dry conditions
D. Kinds of Gymnosperms • 1. Conifers- Coniferophyta • A. leaves are needle-like or reduced to tiny scales for limiting water loss • B. redwoods- tallest trees on earth • C. grow in cool dry regions of the world
2. Cycads- Cycadophyta • A. short stems and palm like leaves • B. cones that produce pollen and seeds on different plants • C. tropics
3. Ginko- Ginkophyta • A. fanshaped leaves • B. male and female gametophytes on different trees • C. Seeds do not develop in a cone
4. Gnetophytes- Gnetophyta • A. trees, shrubs, and vines that produce pollen and seeds in cones that resemble flowers
A. Flowering plants that produce seeds that develop in enclosed structures called fruits • B. Key Features of Angiosperms • 1. flowers- male and female gametophyte, promotes pollination and fertilization, attracts insects and other animals, pathway that allows fertilization by the sperm without water • 2. Fruits- protection for developing seeds, eaten by animals and dispersed from animals bodies • 3. Endosperm- stored food for during development of seeds
C. Types of Angiosperms • 1. Monocots- flowering plants with one seed leaf (cotyledon) and produce flowers with petals in multiples of threes and have parallel veins • 2. Dicots- flowering plants with 2 cotyledons and produce flowers with petals in multiples of two, four or fives and have branching veins
A. All plant parts provide food for humans. Rice, corn, and wheat are cereal grasses and are out most important sources of food • B. Wood is used for making paper, lumber is used for building materials • C. Medicines are made from or derived from plants • D. Plant fibers make paper, rope, and cloth. Wood and cotton are most important