plant cells, tissues and organs
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Plant Cells, Tissues and Organs. Cell Specialization & Cell Differentiation. http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookplantanat.html. http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookplantanat.html. http://earthsky.org/human-world/nate-lewis-on-artificial-photosynthesis. - PowerPoint PPT PresentationTRANSCRIPT
Plant Cells, Tissues and Organs
Cell Specialization & Cell Differentiation
http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookplantanat.htmlhttp://www.emc.maricopa.edu/faculty/farabee/biobk/
biobookplantanat.html
http://earthsky.org/human-world/nate-lewis-on-artificial-photosynthesis http://www-plb.ucdavis.edu/labs/rost/tomato/Roots/rootcell.html
Specialized Cells & Tissues in PlantsTissue: group of specialized
cellsOrgan: Group of several types
of tissues working towards a specific function
Meristem: unspecialized cell that can form specialized cells in plants
Tissues in Plants
Repairing & Replacing Specialized Cells
Buds: Swelling of the stem◦ Terminal Bud –
most active growth, produce Auxin
◦ Lateral Bud – dormant regions, inhibited by Auxin
Plant OrgansLeafStemRootFlower
The LeafDermal tissuePalisade
tissueMesophyll
tissueVascular
bundles
The Leaf – TissuesDermal tissue
◦ Waxy cuticle – limits water loss◦ Protects the leaf
Palisade tissue◦ Prime site of photosynthesis – palisade cells and
chloroplastMesophyll tissue
◦ Loosely packed cells◦ Spaces contain gases such as H2O, CO2 and O2
Vascular tissue◦ Xylem – transports water to the photosynthesizing cells◦ Phloem – transports sugar throughout the plant◦ Small vein branches – every cell gets water and
nutrients
The Leaf – Lower epidermisExchange of gasesGuard cells
◦ Control opening and closing of stomataStomata
◦ Connected to spongy mesophyll◦ CO2 enters, O2 and H2O exits through them
Transpiration – evaporation of water from leaves
Chloroplast
The StemProvides physical
support and transports sap
Composed mainly of xylem tissue◦ Dead tubular hollow
cells fortified with lignin
Vascular bundle◦ Phloem (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 plant’s storage area
The RootsDermal tissue
◦ Root hair – increase surface area for absorption
Ground tissue ◦ Cortex – provide
support◦ Pericycle –
vascular tissue
Types of Roots
Fibrous root• Large surface
area to absorb water
• Stabilize soil• Prevent erosion
& landslides
Tap root• Allows plant
to reach far underground for water
• Anchors the plant
Plants Under Attack
The FlowerReproduction - pollen
and eggsPollination: transfer of
pollen to female parts of flower
Seeds are produced and embedded in fruits
Hormone called ethylene stimulates ripening of fruits
Homework P. 69 # 1, 3, 5 - 7