Plant Form and Function Learning Goal: How are plants structurally adapted for survival? Analyzing how water and nutrients move through a plant (Ch 36 and Investigation 11) Refer to pg , in Holtzclaw Ch 36 in Campbell Media resources AP Inv 11

How and why do water/nutrients move through a plant? You must know: (Ch 36) The role of passive transport, active transport, and cotransport in plant transport. The role of diffusion, active transport, and bulk flow in the movement of water and nutrients in plants (with water potential calculations) How the transpiration cohesion-tension mechanism explains water movement in plants. How pressure flow explains translocation.

How and why do water/nutrients move through a plant? You must know: (AP Investigation 11) The function of stomata in gas exchange in plants. The role of water potential and transpiration in the movement of water from roots to leaves. The effects of various environmental conditions on the rate of transpiration. How to identify xylem and phloem and relate their structure to their function.

How does water and dissolved nutrients get from the roots to the leaves in these tall trees?

Transpiration

How does sugar get from the leaves to the roots in plants for winter storage?

Transpiration Translocation

Try This! What is the similarity between xylem and phloem tissue? What is the difference between xylem and phloem tissue?

Types of Tissue Dermal tissue – outer protective covering Vascular tissue – carries out transportation of materials between roots and shoots ◦ Xylem – transports water and dissolved minerals up from roots into the shoots ◦ Phloem – transports sugars from leaves to other parts of plant (sites of growth) Ground tissue – not dermal or vascular

Xylem Cells – water conducting cells

Phloem Cells – sugar conductive cells

Try This! Explain the difference between passive transport and active transport.

PlasmolysisPlasmolysis an effect of osmosis, which is an example of passive transport

Transport from Roots to Shoots Transport from Roots to Shoots Vocabulary to listen for: ◦ xylem ◦ xylem sap ◦ mycorrhizae ◦ inorganic ions ◦ apoplastic route ◦ symplastic route ◦ plasmodesmata ◦ casparian strip ◦ endodermis cells

Try This: Explain the transport of water and nutrients from roots to shoots

Transport up shoots to leaves: Transpiration through Xylem Transport up shoots to leaves: Transpiration through Xylem Vocabulary to listen for: ◦ transpiration ◦ hydrogen bonds ◦ cohesion ◦ adhesion ◦ solute ◦ stomata ◦ guard cells Question to listen for: ◦ How do (C3) plants prevent excessive water loss in hot, dry environment?

Stomata! Open and Closed

Turgid Flaccid

Try This: Explain the transport of water and nutrients up shoots to leaves

Now… Bioflix! Bioflix Free Response Practice!

How and why does sugar move through a plant? Phloem Translocation in Summer Phloem Translocation in Spring Vocabulary to listen for: ◦ phloem ◦ phloem sap ◦ tranlocation ◦ sugar source ◦ sugar sink ◦ tap root ◦ sieve-tube elements ◦ osmosis ◦ water pressure ◦ bulk flow ◦ active transport ◦ starch

Try This: Explain the transport of sugar from sugar source to sugar sink in spring and late summer

Try This! Remember the equation for water potential? Explain the equation If the in cell A is greater than the in cell B, which way will water move? S P + =

Try This! Remember the equation for water potential? Explain the equation If the in cell A is greater than the in cell B, which way will water move? Water moves from high water potential to low water potential, so from cell A to cell B S P + = Water Potential Solute Potential (lower [solute] means higher solute potential) Pressure Potential (the more water, the higher the pressure potential exerted by the cell wall)

Try This! Predict the effect on water potential of: ◦ Addition of solutes to distilled water ◦ Loss of turgor pressure within a plant leaf S P + =

Try This! Predict the effect on water potential of: ◦ Addition of solutes to distilled water ◦ Loss of turgor pressure within a plant leaf Higher Lower S P + =

Important Vocab: Bulk Flow: the movement of water through a plant from regions of high pressure to regions of low pressure. ◦ Water and solute move through both xylem and phloem tissue by way of bulk flow

Try These Questions: Transpiration has been described as a “necessary evil.” Explain the costs and benefits of transpiration to a plant.