2. Plant Transport Roots absorb water and nutrients.
Roots exchange gases to support cellular respiration.
Transpiration moves water up the xylem of a plant.
Water leaves the plant through the stomatas.
Leaves exchange gases through the stomatas.
Sugar is produced in the leaves
Sugar is transported within the phloem to other parts of the plant.

3. Absorption of Water and Minerals by Roots
Root hairs and mycorrhizae increase surface area to enhance absorption.
Much of the absorption takes place near root tips where epidermis is permeable to water.
Mycorrhizae ‑ (fungi)
Live on and coat the roots of plants, extract nutrients from the soil, and plants absorb minerals from the fungi.

4. Transport of Xylem Sap
Xylem sap is a combination of water and nutrients.
It moves up the vessels at rates of 15 meters per hour or faster.
Xylem sap moves up against gravity by root pressure and transpiraiton.

5. Transpiration
Water moves upwards in the xylem to bring mineral nutrients to the shoot system.
Transpiration is water loss by a plant through stomatas in the leaves.
Water that is lost must be replaced or else leaves will wilt and die.

6. Transpiration
Guard cells control the size of the stomata openings and thus regulate gas and water exchange.
Negative pressure due to evaporation of water draws more water out of the leaf xylem.
Cohesion and adhesion of water moves it up the xylem against the pull of gravity by capillary action.
Water is absorbed by root hairs through osmosis.

7. Control of Stomata Stomatas are holes on lower side of leaves
Guard cells change shape to create stomata for water & gas exchange

8. Control of Stomata Night Time: Sunlight :
Drop in CO2 levels in guard cells causes K+ and water to move in
Guard cells swell, open stomata
Sunlight :
K+ and water move out
Guard cells collapse, close stomata
In a drought, abscisic acid (a plant hormone) causes guard cells to give up K+, causing stomata to close