12.4 Roots
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Transcript of 12.4 Roots
12.4 Roots
Pages 558-563
Roots
Ta Phrohm temple in Cambodia
Function
• Anchor plant• Absorb water and nutrients• Store water and carbohydrates
Types of Roots
Taproot Fibrous roots
Root hairs
• Microscopic hair-like outgrowth from an epidermal cell.
• Increase surface area for absorption
Root cap
• Thick layer of cells produces a slippery substance allowing root to penetrate soil
• Meristem
Cortex
• Parenchyma• Stores carbohydrate• Water passes through cortex
Endodermis
• Wrapped with a wax-like substance.• Form a barrier called the Casparian strip
Vascular cylinder
• Eudicot Monocot• Gymnosperms
Root Specializations
• 80% of plants have mutualistic relationships with mycorrhizal fungi
• Also, nitrogen-fixing bacteria such as Rhizobia are found in the root nodules of legumes
Roots continued…
• Tuberous roots: lateral roots used for storage• For example: yam• Adventitious root: prop root
Uses of roots
• Food• Medicine• Erosion control