1/30/07 L 1 PLANT DIVERSITY CHAPTER 20

1/30/07 L2 Warm-up ► Pick up the 3 sheets on your way in 1. What 3 things do all plants need to survive 2. What is the point of photosynthesis? 3. What are the products and reactants of photosynthesis?

Plant life began in the water and became adapted to land. 1/30/07 L3

Land plants evolved from green algae. ► Plants and green algae have many common traits. – both are photosynthetic eukaryotes – both have the same types of chlorophyll – both use starch as a storage product – both have cell walls with cellulose 1/30/07 L4

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6 PLANTS 1. M ulticellular (many celled) Eukaryotic (nucleus) 2. A utotrophic (make their own food) contain chlorophyll in chloroplast 3. C ell walls contain cellulose 4. S exual and Asexual reproduction

1/30/07 L7REVIEW C 6 H 12 O 6 Glucose

1/30/07 L8 NON-VASCULAR Plants Seedless NON-VASCULAR Plants Seedless 1. Example Moss have No tubes or vessels to carry water etc.

1/30/07 L9 2. Must live in wet places water passes through cells by osmosis.

1/30/07 L10 3. No true roots – have rhizoids – anchor plant

1/30/07 L11 VASCULAR PLANTS 1.Examples are Ferns, Pines, Flowering plants

1/30/07 L12 2. Have vascular tissue similar to veins 3. Xylem – moves water up (dead cells) 4. Phloem – moves food down (live cells)

1/30/07 L13 Vascular Tissue

1/30/07 L14 VASCULAR PLANTS WITHOUT SEEDS 1. Ferns 2. No seeds

1/30/07 L15 FERNS a. Frond – leaf b. Rhizomes – underground stem

1/30/07 L16 c. Sorus – produces spores

1/30/07 L17 d. Fiddleheads – unfurling fern fronds

1/30/07 L18 VASCULAR PLANTS WITH SEEDS 1. Produce seeds in cones or flowers

1/30/07 L19 2. Have true roots, stems, leaves 3. Fertilization – pollen enters ovary and combines with ovule (egg)

1/30/07 L20 4. Oldest Plant Alive – Ginkgo biloba (Have seeds)

1/30/07 L21 GYMNOSPERMS 1. P ine trees, firs, evergreens 2. H ave cones (no flowers) 3. M ale cone produces pollen 4. F emale cone produces seed after pollination 5. L iterally means “naked seed” male Female

1/30/07 L22 GYMNOSPERMS

1/30/07 L23 ANGIOSPERMS 1. F lowering plants, fruit trees 2. M ost abundant type of plants 3. S eeds are contained in and protected by fruit

Plants have adaptations that allow them to live on land. ► Challenges of living on land have selected for certain plant adaptations. ► A cuticle allows plants to retain moisture.  waxy, waterproof layer  holds moisture in –

► Stomata are tiny holes in the cuticle. stoma –can open and close –allow air to move in and out

► Plants have adaptations that prevent animals from eating them. –defensive chemicals –spines and thorns

1/30/07 L27 Plant Adaptations ► Aquatic plants have to be able to tolerate mud.  To take in enough oxygen, they have tissues with large air space and stomata on the upper side of the leaves. ► Salt tolerant plants can withstand salt concentrations in the soil far greater than normal plants. ► Epiphytes are plants that do not root in the soil, their roots get water from the air. ► Many plants defend themselves against insect attack by making compounds that ward off animals.

1/30/07 L28 Leaf Modifications ► Cactus spines are modified leaves that help reduce water loss from the plant and provide protection from predators. ► Carnivorous plants, like the pitcher plant have leaves with adaptations that can trap insects or other small animals. ► Leaves often function as water or food storage sites.  This adaptation ensures the long-term survival of the plant when water resources are scarce.

1/30/07 L29 Response to Stimuli - Tropism 1. Phototropism – response of a plant to light

1/30/07 L30 2. Gravitropism – plant response to gravity

1/30/07 L31 ► Positive – toward the stimulus ► Negative – away from the stimulus Roots grow toward the earth, positive gravitropism. Roots grow away from light, negative phototropism

1/30/07 L32 3. Thigmotropism – plant response to touch

1/30/07 L33 Photoperiodism – plant response to daylight length (time)