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Transpiration

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Closer Look: Movement of Water Up Xylem Vessels

Concept 1: Hydrogen Bonding

Concept 2: The Process of Transpiration

Test Yourself

Concept 3: How Do Guard Cells Function?

Concept 4: Guard Cell Function Animation

Concept 5: Transpiration and Photosynthesis

Concept 6: Factors That Affect the Rate of Transpiration

Design of the Experiment

Experiment 1: An Overview of the Experiment

Experiment 2: How to Calculate Leaf Surface Area

Analysis of Results I

Key Concepts II

Analysis of Results II

Guard Cell Function

Stomatal closing

1.	Potassium ions move out of the vacuole and out of the cells.
2.	Water moves out of the vacuoles, following potassium ions.
3.	The guard cells shrink in size.
4.	The stoma closes.

Stomatal opening

1.	Potassium ions move into the vacuoles.
2.	Water moves into the vacuoles, following potassium ions.
3.	The guard cells expand.
4.	The stoma opens.