Differ from seedless plants because… – Produce seeds, which nourish and protect young sporophytes – Gametophytes form within sporophyte – Sperm forms within and transported by pollen (via wind, animals) Seed Plants

Angiosperms Flowering Seed Plants

The most abundant plant today Wind and/or animals for pollination “Fruit” surrounds/protects seeds Monocots & Dicots Angiosperms

Monocots – Seeds with 1 cotyledon (seed leaf) grasses, onions, lillies – Leaves have parellel veins – Vascular tissue in stem is scattered Dicots – Seeds with 2 cotyledons (seed leaves) beans, peanuts, peas, roses – Leaves have branching veins – Vascular tissue in stem arranged in ring 2 Classes of Angiosperms

Di- cots

Provide animals with food Food crops for humans Building materials Clothing Perfumes Medicines Importance of Angiosperms

Adaptations for sexual reproduction – Sepals Modified leaves that protect bud – Petals Attract insects and other animals to flower – Stamen Male reproductive part; filament and anther – Pistils Female reproductive part; stigma, style, & ovary Flowers

Pistil Reproduction in Flowering Plant -pollination occurs -pollen tube forms to the ovule (contains an egg) -sperm (pollen) fertilize the egg (ovule) -fertilized egg develops into young sporophyte, surrounded by seed -ovary forms fruit that protects the seed

Gymnosperms Nonflowering Seed Plants

Do not have flowers or fruits; seeds usually protected by a cone Gymnosperms conifers cycads

Gymnosperms (cont) ginkgoes gnetophytes

Life Cycle of Gymnosperms

Building material Paper products Resin to make soap, turpentine, paint, ink Yew-anticancer medication Anti-allergy Aesthetics (gardens, parks) Importance of Gymnosperms

Root & Shoot System – Xylem Vascular tissue that transports water and minerals from root to the shoot – Phloem Transports food molecules (sugar) to all parts of plant Root Functions – Supply water & dissolved minerals – Secure plant in soil – Store surplus food (as sugar or starch) Root Systems – Taproot (dicots & gymnosperms) or Fibrous (monocots) Structures of Seed Plants

Functions – Support, transport, & some store materials Herbaceous – Soft, thin, flexible – Wild flowers, tomatoes, corn Woody – Made of wood & bark – Growth rings Large (light) xylem cells in spring/summer, small (dark) in fall/winter Stems

Function – Make food for plant Structure – Cuticle – Stomata – openings in epidermis (CO 2 ) Adaptation – Protection-spines on cactus – Nutrients-insect eaters for nitrogen Leaves

Tropisms – Growth in response to a stimulus – Positive (toward) or negative (away) Phototropism – (positive) towards light Gravitropism – Root tips – positive, toward center of Earth – Shoot tips – negative, away from center of Earth Plant Response to the Environment

All trees lose leaves – Evergreen (pine, holly, etc) Some leaves year round Thick cuticle Protects from dry, cold weather – Deciduous (maple, oak, elm) Lose leaves each year – Before winter in cooler climates – Before dry season in warmer climates Help plant to survive (less to support) Seasons and Leaf Loss