PLANTS
Characteristics 1. Multicellular 2. Eukaryotes 3. Photosynthesis 4. Cells walls have cellulose 5. Most cuticle (waxy, waterproof coating)
2 Types of Plants Nonvascular Most primitive, rely on water coming to them close to the ground reproduce using spores example: moss Vascular contain vascular tissue that transports water and minerals can grow tall vascular tissues (xylem and phloem) example: oak tree
Parts of a Vascular Plant 1. Roots – penetrate soil organ that absorbs water and minerals 2. Stem a. Transport food, water, and other materials b. Organs for food storage c. Photosynthesis Leaves a. photosynthesis
Typical Reproductive Strategies 1. Seeds – organ that contain an embryo, food, & protective coat 2. Reproduce by spores/seeds
Which is vascular and which one is nonvascular? B.
2 Groups of Vascular Plants Gymnosperms needlelike or scale-like seeds reproductive structures in cones most are evergreen, some are deciduous prevents water loss Examples: pine, spruce, and conifer trees Angiosperms (vessel seed) flowering plants ”vessel seed” produce and store their seeds in an ovary (will become fruit) examples: roses, apple trees, geraniums
Monocots Grass, orchid and lily Dicots Shrubs, herbs, and veggies
MONOCOTS Angiosperms Single seed leaf (cotyledon) Leaf veins are parallel flowers/petals grow in groups of 3
DICOTS Angiosperms 2 seed leaves (cotyledons) Leaf veins are branched (net-like) flowers/petals grow in groups of 4 or 5 Majority of flowering plants
Flower Reproductive organ of the plant Male and female parts Stamen – male Pistil - female
Plant Reproduction Stamen produces pollen & it moves away from plant (wind, pollinators) Pistil pollen lands on the pistil of another plant (called pollination) fertilizes the egg within the ovary (called fertilization) flower petals fall off ovaries develop into a fruit that encloses the seeds Are fruits always edible? NO! ex. Helicopters, acorns, dandelions
Asexual Reproduction Vegetative propagation Duplicate themselves Strawberry plants send out runners grow into new plants Plant clippings can grow into new plants Potato will grow into a new plant
Most plants reproduce sexually and asexually Most have male and female parts
Germination Seed begins to sprout (temperature and moisture changes)
Vascular Tissues • Xylem - transport of water and minerals (up) • Phloem - transport of food (down)
Roots Taproots Accumulate & store food Beets, carrots Fibrous roots Small branching roots from a central point Prop roots Originate from above Help support it corn
Stems Herbaceous stems Woody stems Green Soft, flexible Photosynthesis Petunias, impatiens Woody stems Brown, made of wood Hard, rigid Trees, shrubs
Leaf Cross Section
Leaves Transpiration: loss of water through the stomata (or stoma) on the leaves Guard Cells – surround and control size of a stomata (or stoma); water movement by osmosis Stomata – opens and closes; helps reduce water loss
Plant hormones A chemical produced and transported to another part of the plant (change) Auxins Inhibit growth of side branches; cause delays Gibberellins Promotes growth; germination Cytokinins Stimulate cell division Ethylene Gas Promotes ripening (fruits)
Plant Tropisms + moves toward stimulus - moves away from stimulus A plant’s response to an external stimulus + moves toward stimulus - moves away from stimulus Phototropism – moves toward light (auxin on opposite side)
Gravitropism – response to gravity (stems = -) (roots = +) Thigmotropism – response to touch Nastic Movement – responsive movement; does not depend on the stimulus (venus fly trap)
Growth Annuals – 1 life cycle in 1 growing season Biennials – takes two growing seasons Perennials – live several years; reproduce several times