Plant Evolution & Roots By: Adi Beal and Madi McDade Importance of Plants Botany- the study of plants Plants have a lot of diversity Steps of Evolution 1st Step: Multicellular 2nd Step: Move onto Land 3rd Step: Vascular System 4th Step: Seeds 5th Step: Flowers & Fruits 1st Step: Multicellular Aquatic organisms Get support from water Before multicellular Volvox Colony of individual cells that cooperate First multicellular plant Red Algae Rhodophyta Volvox Video https://www.youtube.com/watch?v=He9FSeGRi3A 2nd Step: Move onto Land Mosses had no adaptations for life away from water First terrestrial plants Bryophyta Need ozone to block out UV rays which damage DNA More cellulose for structure Get water through roots UV Damage Diagram 3rd Step: Vascular System True roots and stems Xylem Phloem Waxing coating on leaves to conserve water Obtain CO2 through stomata, which close at night to prevent water loss Stomata Diagram 4th Step: Seeds Dispersed by wind, water, and animals Spore-individual cells that clump and each contain embryo, an endosperm, and seed coat Gymnosperms Seeds are not covered by a true fruit Gymnosperms Activity http://studyjams.scholastic.com/studyjams/jams/science/plants/gymnosper ms.htm Seed Dispersal Diagram Seed Video https://www.youtube.com/watch?v=6loGKPKDqCw 5th Step: Fruits & Flowers Fruit- plant structure which results from the pollination of a flower and contains a seed Fruit may protect the seed Angiosperms- flowering plant that produce seeds enclosed in a fruit Flowers produce the reproductive part of the plant Flowers attract pollinators like bees, bats, and butterflies Angiosperm Activity http://studyjams.scholastic.com/studyjams/jams/science/plants/angiosperm s.htm Plant Reproduction Diagram Plant Evolution Video https://www.youtube.com/watch?v=yL1o49YGhtM Plant Adaptations Waxy Cuticle Stomata Reproduction Spores Seeds Vascular Tissues Xylem Phloem Why Do Plants Adapt Activity http://studyjams.scholastic.com/studyjams/jams/science/plants/plantadaptations.htm Monocot vs. Dicot Flowers Monocot Parts in threes or multiples of threes Dicot Parts in fours or fives or multiples of fours and fives Monocot vs. Dicot Leaves Monocot Smooth often narrow shapes with parallel veins Dicot Oval or hand-like shapes with neck-like veins Monocot vs. Dicot Vascular Tissue Monocot Vascular bundles scattered through stem Dicot Vascular bundles arranged in ring around stem Monocot vs. Dicot Root Pattern Monocot Fibrous root system Dicot Taproot system Monocot vs. Dicot Embryo in Seed Monocot Embryo has one cotyledon (seed leaf) Dicot Embryo has two cotyledons (seed leaves) Monocot Examples Lilies Tulips Bananas Pineapples Onions Corn Rice Oats Dicot Examples Beans Lettuce Oak Maple Roses Daises Monocots vs. Dicot Video https://www.youtube.com/watch?v=gI2RxzAT-ww Monocot vs. Dicot Activity http://www.math4childrenplus.com/monocots-and-dicots/ Tissue Types 1. 2. Vascular tissue 1. Xylem- transports water to plant 2. Phloem- transports food and minerals Apical Meristem- responsible for upward growth in plant and produces cells that will eventually specialize Meristem Types of Roots 1. Primary Root- the first root that appears out of a seed 2. Taproot- primary root grows thicker and longer with secondary roots growing off of it 3. Fibrous root- primary root branches off into many small roots 4. Lateral root- extend horizontally from primary root and anchor plant securely in the soil 5. Aerial root- root exposed to air and absorbs moisture 6. Adventitious root- a root that grows above ground or in an odd place Root Types Root Structure 1. Root Cap- hard protective layer, prevents breakage as plant pushed through soil, secretes slimy lubrication 2. Root hairs- increase surface area of root so more water and nutrients can be absorbed, main entry point of water 3. Epidermis- waterproof outermost layer, protection 4. Cortex- many layers of parenchyma cells, stores starch for energy 5. Endodermis- innermost cylinder of cortex, waterproof, regulates movement of water and minerals into vascular tissue Root Structure (cont.) 6. Pericylce- outermost layer of cells of the steel, goes through cell division creating root hairs 7. Root system- constantly provides the stem and leaves with water and dissolved minerals 8. Root tip- where mitosis occurs 9. Permeable membrane-layer of the cell where water and nutrients can pass through Root Structure Diagram Root Growth https://www.youtube.com/watch?v=eDA8rmUP5ZM Root Activity http://studyjams.scholastic.com/studyjams/jams/science/plants/rootsstems.htm Fun Facts!! Roots are the parts of plain that grow down into soil or water, anchoring it and soaking up all the water and minerals the plant needs to grow. In some plants such as beetroots, the roots are also a food store. When a seed begins to grow, its first root is called a primary root. This branches into secondary roots. Roots are protected at the end by a thimble shaped root cap as they probe through the soil. How plants live On every root there are tiny hairs that help it to take up water and minerals. Some plants, such as carrots, have a single large root, called a taproot, with just a few fine roots branching off. Some plants, such as grass, have lots of small roots, called fibrous roots, branching off in all directions. Some kinds of orchid that live on trees have ‘aerial’ roots that cling to the branches. Mistletoe has roots that penetrate its host tree. Roots are delicious when boiled or pickled. The roots of the South African wild fig tree can grow 120 m down into the ground.