plant cells, tissues and organs

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Plant Cells, Tissues and Organs

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Plant Cells, Tissues and Organs. Cell Specialization & Cell Differentiation. - PowerPoint PPT Presentation


Plant Cells, Tissues and Organs

Plant Cells, Tissues and Organs

Cell Specialization & Cell Differentiation cell conducting vessel element in mahogany woodGuard cellPhotosynthetic cellEpidermal cell (root hair of tomato)2Specialized Cells & Tissues in PlantsTissue: group of specialized cellsOrgan: Group of several types of tissues working towards a specific functionMeristem: unspecialized cell that can form specialized cells in plants3Tissues in Plants

Repairing & Replacing Specialized Cells

Buds: Swelling of the stemTerminal Bud most active growth, produce AuxinLateral Bud dormant regions, inhibited by Auxin

Plant OrgansLeafStemRootFlower

The Leaf

Dermal tissuePalisade tissueMesophyll tissueVascular bundles

The Leaf TissuesDermal tissueWaxy cuticle limits water lossProtects the leafPalisade tissuePrime site of photosynthesis palisade cells and chloroplastMesophyll tissueLoosely packed cellsSpaces contain gases such as H2O, CO2 and O2Vascular tissueXylem transports water to the photosynthesizing cellsPhloem transports sugar throughout the plantSmall vein branches every cell gets water and nutrientsThe Leaf Lower epidermisExchange of gasesGuard cellsControl opening and closing of stomataStomataConnected to spongy mesophyllCO2 enters, O2 and H2O exits through themTranspiration evaporation of water from leaves


The StemProvides physical support and transports sapComposed mainly of xylem tissueDead tubular hollow cells fortified with ligninVascular bundlePhloem (living porous cells) exchanges materials with neighbouring cells

The RootsAnchor a plant to the ground

Allow water and minerals uptake from the soil

Some also act as plants storage area

The RootsDermal tissueRoot hair increase surface area for absorption Ground tissue Cortex provide supportPericycle vascular tissue

13Types of RootsFibrous rootLarge surface area to absorb waterStabilize soilPrevent erosion & landslides

Tap rootAllows plant to reach far underground for waterAnchors the plantPlants Under Attack

The FlowerReproduction - pollen and eggsPollination: transfer of pollen to female parts of flowerSeeds are produced and embedded in fruitsHormone called ethylene stimulates ripening of fruits

Homework P. 69 # 1, 3, 5 - 7