8 Primary Root Definition: the first root produced by a germinating seed Arises from the radicle of the seedling, which grows to form lateral rootsAxial StructureNo Nodes and internodesLimited area near the root tipNo nodes and internodes- no leaves or leaf like structures
9 Lateral or Secondary Roots Definition: roots that grow horizontally away from the primary root.
10 Adventitious RootsDefinition: Roots developed from the stem that replace the primary root after it dies at an early stage.These roots are equal in sizeGive rise to lateral rootsDevelop in places other than nodesCan form cuttings and rhizomesDo not undergo secondary growth
11 Fibrous RootsDefinition: root structures in which the primary and lateral roots develop equally so that there is not a definite taproots.Many finely branched secondary rootsPrimary root is short livedDo not branch profusely, are shallow and spread horizontally cannot provide strong anchorageMain root system of monocotsShallow roots cover a large areMore effective absorption of water and mineralsRoots hold the soil to prevent erosion
12 Tap Roots Definition: continuation of the primary root. Ideal for anchoragePenetration is greater for waterStorage area for food made by photosynthesisBares many branchesRemains undergroundUsually found in dicots
14 Storage Roots Definition: structures which are used for food storage. Swollen portions of primary roots or lateral rootsUsually involves secondary growth in which the secondary xylem or phloem become filled with food reserves
15 Aerial RootsDefinition: short roots that grow horizontally from the stemsFasten the plant to a supportFunction as prop roots or anchorageMore common in tropics
16 What are roots composed of? Root capApical meristemRegion of elongationRegion of differentiationXylemPhloemRoot hairs
18 DefinitionsRoot cap: covers the apical meristem and protects it from damage.Apical meristem: region of active cell division; the growing point of the plant.Region of elongation: cells here grow longitudinally which causes the root to grow longer.Region of differentiation: the region of mature primary tissues which is an area of active water and mineral absorption.Xylem: transports water and nutrients upward.Phloem: transports carbohydrates and sugars downward.Root hairs: increase surface area and aid in absorption.
19 Root HairsDefinition: tiny one celled hair like extensions of the epidermal cells located near the tips of the roots where vascular tissues have formed.Increase surface areaAbsorb water and minerals from soil
30 Epidermis Cuticle Stomata Guard Cells Waxy substance covers the leaves and stemsWaterproof layer that keeps water in plantsStomataOpenings in the epidermisExchange of gasesGuard CellsTwo cells located on each side of stomataOpen and closes stomata
32 Mesophyll Layer Palisade mesophyll Primary site of photosynthesis Spongy mesophyllContains air and chloroplastsSite of photosynthesis and gas exchange
33 Veins or vascular bundles Located in spongy mesophyllPhloem tissues conduct food from photosynthesis to rest of plantXylem tissues conduct water and minerals up to cells in leaves and stems
34 Parts of a Flower Peduncle Receptacle tip of the stalk where the flower beginsReceptaclestarts at the peduncle and acts as a base to which all other parts of the flower are attached
35 Parts of a Flower Sepals Petals Outer covering of the flower bud Protects the stamens and pistils when flower is in bud stageCollectively called calyxPetalsInner whorl of leavesProtects stamen and pistilsAttracts pollinating insectsKnown collectively as the corolla
36 Male Reproduction: Flower StamenMale organsThe number per flower variesComposed of two parts:Anther- produces pollenFilament- supports the anther
37 Female Reproduction: Flower PistilFemale organsThere can be one or moreThree parts:Stigma- holds the pollen grains and is stickyStyle- connects the stigma to the ovaryOvary- enlarged portion at base of pistil and produces ovules which develop into seeds
38 The peduncle is the tip of the stalk where the flower begins The peduncle is the tip of the stalk where the flower begins. The receptacle starts at the peduncle and acts as a base to which all other parts of the flower are attached.
39 ReferencesComparison of Root, Stem and Leaf Structure and Function in Dicots. (n.d.). Welcome to Hillfield Strathallan College. Retrieved May 21, 2012, fromPrimary Root Structure and Development . (n.d.). EEOB. Retrieved May 21, 2012, fromRoot Structure and Function. (n.d.). Botanical Science . Retrieved May 21, 2012, from tructure/RootsStructure.htmRoot System. (n.d.). BIO. Retrieved May 21, 2012, fromThe Structure of Plants . (n.d.). The Structure of Plants . Retrieved May 21, 2012, from homepage.smc.edu/hodson_kent/plant_growth/Angiosperms/ID/basics.htm