What were some challenges that plants had to overcome as they moved to land? Drying out in the sun Conserving water Reproduction without water

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1 Classification of Plants (Ch. 22) The 3 major characteristics that make an organism a plant are: Multicellular eukaryote Cell walls with cellulose Carry out photosynthesis Plants most likely evolved from: Multicellular green algae What were some challenges that plants had to overcome as they moved to land? Drying out in the sun Conserving water Reproduction without water The 4 groups of plants are: 1. Mosses 2. Ferns 3. Gymnosperms (cone-bearing)_ 4. Angiosperms (flowering) The 3 features used to group the plants are: 1. water-conducting tissues 2. seeds 3. flowers For each group of plants, identify the major characteristic of that group. Give examples. Vascular or Seedless Group Nonvascular or Seeds Examples Bryophytes Non-vascular no seed moss; liverwort Ferns Vascular no seed horsetail ferns Gymnosperms Vascular seeds conifers; cycads Angiosperms Vascular seeds flowering plants

2 (diagram p. 554) Evolutionary Relationships of Plants Conifers- Gymnosperms Flowers Flowering Plants- Angiosperms Ferns Seeds Mosses Vascular System Multicellular green algae Parts of Plants (Ch. 23) What are the 3 main organs and their functions? Roots- absorb water and nutrients Leaves Photosynthetic Stems-support; connect root + leaves; carry H2O + nutrients Tissues: name the 3 main types and their functions: Dermal: outer covering of plant o cuticule: thick waxy covering, conserves water; o root hairs: small cells on roots, increase survace area for water absorption Vascular: transport system used to move water and nutrients through the plant xylem: transports water

3 phloem: transports nutrients + carbs from photosynthesis Ground tissue-cells between dermal and vascular tissue Roots: Used for: 1) Absorption of minerals and water from the soil. 2) Storage of starches (vegetables) 3) Anchor to ground 4) 2 main types of roots: taproot grow long and deep to reach water below the surface. Ex. Carrots, radishes fibrous branched root system that grows close to the surface helps prevent soil from being washed away by rain. *Plants can have taproots, fibrous roots or both* 5) Apical Meristem: area of root where cell division and growth occurs. Stems: Function: produce leaves, branches, and flowers; used for support and transport of substances between leaves and roots. Leaves: Function: Absorb light and carry out photosynthesis Special structures Stomata opening in leaf to allow exchange of O2, CO2 and water vapor Guard cell regulates opening of the stomata and respond to conditions in the environment (wind, temperature) to maintain homeostasis within leaf. Underside of leaf

4 Photosynthesis: write the equation below. Explain how the following structures influence photosynthesis Equation: CO2 + H2O + Light C6H12O6 + O2 Xylem: transports water needed for reaction to occur. Phloem: transports glucose from leaves to roots for storage. Stomata & Guard Cells: regulates the amount of CO2 gases & H2O needed for photosynthesis to occur. Leaf: contains chloroplasts, chlorophyll, + enzymes needed for photosynthesis Transpiration loss of water through stomata When water is abundant, it flows from roots to leaves and guard cells respond by opening stomata to release excess water When water is scarce, guard cells respond by closing stomata to limit transpiration High transpiration rates can lead to wilting. Turgor Pressure: Turgor pressure is the pressure of a plant cell s contents against the cell wall. This gives the plant its rigid structure. What are some conditions which could cause Turgor Pressure to decrease, thus causing the plant to wilt? Plant dehydration: the vacuole loses water, causing turgor pressure to decrease and the plant will wilt Describe a monocot: 1 seed leaf; parallel veins; flower multiples of 3; Fibrous roots Describe a dicot: 2 seed leaves; branched veins; flower multiples of 4 or 5, tap root Define pollen grain: male sex cell Reproduction (Ch. 24) In gymnosperms, the male cone is called the _pollen_ cone and the female cone is called the _seed cone. In angiosperms, the reproductive organs are the flowers. The 4 kinds of specialized leaves: 1. Sepals_ 2. _Petals 3. Carpel/Pistil (female)_ 4. Stamens (male)_ Seeds Define a fruit: ripened ovary containing angiosperm seeds. Fruit protects seed, helps in dispersal. Give 10 examples of fruits: apple, pear, beans, grape, peach, pea, strawberry, tomato, corn, cucumber, grape, pear Compare and give examples of fleshy and dry fruit: Fleshy: apple Dry: maple, ash

5 Name 3 methods of seed dispersal and give examples: Animals insects, birds, bats + other mammals Wind maple, dandelion Water Germination Define germination: early growth stage of the plant embryo Describe the 3 steps of germination: 1. absorb water 2. food storing tissues swell, crack open seed coat 3. young root emerges, begins to grow Growth (Ch. 25) What is the role of hormones? Chemical substances that control: 1- pattern of growth and development. 2- plant s response to environmental conditions For each hormone listed below, give the effect that it has on the plant: auxin (3): growth- branching; phototropism- bend toward light; gravitropism root growth downward cytokinins (2): stimulate cell division; growth of lateral buds; cause dormant seeds to sprout gibberellins (1): growth hormone-dramatic increase in size especially in stems and fruit ethylene (1): stimulates fruit to ripen Responses For each type of response listed, explain and give an example. Tropism response to external stimuli Gravitropism: response to gravity. Shoots grow up-against gravity. Roots grow down- with force of gravity Phototropism response to light Thigmotropism response to touch: growing tip grows + twist Around object; stunted growth Photoperiodism: response to amt of day light (seasonal changes) winter dormancy: plant growth + activity decrease or stops. leaf abscission: layer of cells forms at petiole; seals leaf off from plant s vascular system

6 Adaptations (Ch. 25) Name 3 ways plants have adapted to life in the water: Air-filled spaces in tissues, allow for uptake + diffusion of oxygen Seeds that float in water Bald cypress- knees protrude above water, bring O2 to roots Name 1 way plants have adapted to salty conditions: Leaves have special cells that pump salt out at tissues and onto leaf surface washed off by rain Name 3 ways desert plants have adapted: Extensive roots to capture water, w/ many root hairs (cacti) Leaves become spines Thick green stems- photosynthesis, store H2O, seeds dormant for years germinate with rain. Name 2 ways plants have adapted to poor soil: Carnivorous- pitcher plant, Venus fly trap (nutrient poor/nitrogen poor soil) Parasitic extract water and nutrients directly (examples-mistletoe) Name 1 way plants have adapted to grow on other plants: Epiphytes- grow directly on bodies of other plants, get water from rain, make own food. Ex: Spanish moss Name 1 way that plants have adapted to help fight insects: Manufacture compounds that have effect on insects (poisons) Insect hormones-prevent insect from reproducing

7 Flower diagram: (p. 612) Stamens Stigma Pistil/Carpal Anther Style Filament Ovary Ovules Sepal Petal Stamen : anther + filament Carpal or pistil : stigma + style