Post on 30-Dec-2015
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Plant Form & FunctionPlant Anatomy
AP BiologyBloomington High School
Plant Tissues
• Ground tissues• Parenchyma
– Thin walls– Storage– Photosynthesis– Secretion
Plant Tissues
• Ground tissues• Collenchyma
– Thick, flexible walls
– Support
Plant Tissues
• Ground tissues• Sclerenchyma
– Thick walls– Support
Plant Tissues
• Dermal Tissue• Epidermis
– Cover surface of plant– Guard cells-
Plant Tissues
• Vascular Tissue• Xylem
– Transports water & minerals
– Tracheids– Vessel elements
Plant Tissues
• Vascular Tissue• Phloem
– Transports food– Sieve-tube members– Companion cells
Primary vs. Secondary Growth
• Primary Growth• Growth in length• Apical meristems• Tips of roots & shoots
Primary vs. Secondary Growth
• Secondary Growth• Growth in width• Lateral meristems• Vascular cambium• Cork cambium
Root Tip
• Root cap• Protects apical
meristem
Root Tip
• Zone of cell division• Cells divide• Apical meristem
Root Tip
• Zone of elongation• Cells absorb water &
elongate
Root Tip
• Zone of maturation• Cells mature• Perform specific
functions• Cells differentiate• Root hairs
Herbaceous Dicot Stem
• Epidermis• Outer layer
of cells• Provides
protection
Herbaceous Dicot Stem
• Cortex• Ground
tissue• May contain
chloroplasts
Herbaceous Dicot Stem
• Pith• Storage• Provides
support through turgor pressure
Herbaceous Dicot Stem
• Vascular Bundle
• Xylem & phloem
• Occur in rings
Herbaceous Dicot Stem
• Vascular Bundle• Bundle cap• Cells
– Dead– Fibrous– Thick walled
• Sclerenchyma cells
• Provide support
Herbaceous Dicot Stem
• Vascular Bundle• Phloem• Transports food• Sieve-tube members
– Long– Living cells
• Companion cells– Small– Parenchyma cells
Herbaceous Dicot Stem
• Vascular Bundle• Xylem• Transports water• Tracheids
– Dead– Thick walled
• Vessel elements– Large diameter– Dead
Herbaceous Dicot Stem
• Vascular Bundle• Vascular cambium• Between xylem &
phloem• Cells divide to form
xylem & phloem
Woody Stem
• Pith
Woody Stem
• Xylem• Wood
Woody Stem
• Xylem• Wood• Summer wood
– Small cells– Less water
• Spring wood– Large cells– More water
Woody Stem
• Xylem• Annual rings• 1st year’s growth• 2nd year’s growth• 3rd year’s growth
Woody Stem
• Bark• Phloem• Cortex
Woody Stem
• Vascular cambium
• Between xylem & phloem
• Produces newxylem & phloem cells
• Secondary growth
Dicot Root Cross Section
• Epidermis• Absorbs water• Root hairs
increase surface area for water absorption
• In older roots provides protection
Dicot Root Cross Section
• Cortex• Bulk of root• Stores starch
Dicot Root Cross Section
• Vascular cylinder• Stele• Xylem & phloem• Outlined by
endodermis
Dicot Root Cross Section
• Vascular cylinder• Xylem• Large cells• Dead• Transport water
& minerals
Dicot Root Cross Section
• Vascular cylinder• Phloem• Small cells• Transport food
Dicot Root Cross Section
• Vascular cylinder
• Endodermis• Casparian strip
– Waxy– Forms barrier
• All water must pass through endodermis before entering stele
Leaf
• Upper epidermis• Provides
protection• Cuticle
– Waxy– Decreases
water loss
Leaf
• Lower epidermis• Contains stomata
– Holes
– Allow CO2 in &O2 & H2O out
– Surrounded byguard cells
Leaf
• Palisade mesophyll• Parenchyma
cells• Tightly packed• Photosynthesis
Leaf
• Spongy mesophyll• Parenchyma
cells• Loosely
arranged• Photosynthesis• Air spaces
Leaf
• Vascular bundle• Veins• Xylem (red) &
phloem (green)• Bundle sheath
cells surround bundles