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Plant. Structure and Function. Angiosperm structure. Root system depends on shoot for organic molecules Shoot system depends on root for water and nutrients Organ vs. tissue. Plant tissues. Nonwoody plants: Epidermis Wood plants: Periderm replaces epidermis
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Plant Structure and Function
Angiosperm structure • Root system depends on shoot for organic molecules • Shoot system depends on root for water andnutrients • Organ vs. tissue
Plant tissues • Nonwoody plants: Epidermis • Wood plants: Periderm replaces epidermis • Water/nutrient absorption vs. cuticle • Root and stem vascular tissue: stele • Ground tissue INTERNAL to vascular: pith • Ground tissue EXTERNAL to vascular: cortex • Protoplast: Cell contents EXCLUDING the cell wall
5 – Leaf structure (688) 6- Stem structure (687) 7 - Root structure (685) 1 – Leaf form follows function 2 – Stem form follows function 3 – Root form follows function For your assigned organ, either list examples of form follows function OR describe the basic structure of it (including tissues and difference between monocot and eudicot). Be prepared to explain
Plant growth • Indeterminate vs. determinate growth • Annuals vs. biennials vs. perennials • Apical meristems primary growth • Lateral meristems secondary growth • When does growth happen?
Plant concept map • Start your concept map with the following categories • Think carefully how you want to integrate the diagrams. They can be hand drawn or cut out from the internet. Many terms can be used to label diagram (still need to be connected to 2 other terms with connecting phrase) • Over the weekend, write out terms, and begin finding connections between terms Plant Reproduction Structure Regulation transport
Transport regulation: Root pressure • Aquaporins: Increase the RATE of osmosis • Cell membrane vs. vacuolar membrane (tonoplast) • Symplast vs. apoplast
Diffusion is only efficient over VERY small distances (less than 100 μm) Bulk flow (driven by pressure) Pathway of water and minerals Guttation: Increasing SA: Root hairs and mycorrhizae Root pressure Root pressure can only push water up 2-3 m. What mechanism delivers water to the top of a Redwood tree?
Push (+ Ψ) or pull (- Ψ)? Ψ outside leaf < Ψ inside leaf Direction of water vapor? TRANSPIRATION! Transpiration How could this allow water to move upward? Film lining air spaces curves as vapor leaves ↑ radius ↓ Ψ
Transpiration-Cohesion • Water pulled toward airspace film, which pulls on COLUMN of water molecules (cohesion and adhesion)
Transpiration lab instructions • Place plant into tubing UNDER water. Check to ensure there are no air bubbles. Use petroleum jelly to seal • Prediction, interpretation of conditions • Why change units to mL/m2? • Mark which data must be filled in
Stomatal opening/closing • Photosynthesis/transpiration compromise • Sunny, warm, windy days increase evaporation, why? • Adaptations to water loss: Cuticle, biochemical pathways (xerophytes)
Light: Stimulates membrane proton pumpsK+ accumulation Osmosis makes guard cells turgid Stomata open • Depletion of CO2 stomata open • Circadian rhythm,
Double fertilization • 1 sperm egg (zygote- 2n) • 1 sperm 2 polar nuclei (3n) endosperm
Seed structure • Ovule seed • Ovary fruit (controlled by hormones) • Simple (peach, pea pod, nut) vs. aggregate (raspberry) vs. multiple (pineapple)
Phototropism experiment (Went)Extracted the chemical messenger (auxin)
Plant hormones • Know table on pg. 794. Auxin, cytokinins, gibberellins, abscisic acid, ethylene