Transpiration

Question 1

How does wind speed effect transpiration?

Answer 1

Transpiration increases as wind speed increases

Question 2

How does humidity effect transpiration?

Answer 2

• Transpiration increases as humidity decreases
• Very humid air has a smaller concentration gradient

Question 3

How does temperature effect transpiration?

Answer 3

• Transpiration increases as temperature increases
• Water evaporates quickly on a hot day

Question 4

What 5 environmental conditions effect transpiration?

Answer 4

• Temperature
• Humidity
• Wind Speed
• Light Intensity
• Water Supply

Question 5

Where does water leave the plant in transpiration?

Answer 5

The leaves

Question 6

Define transpiration

Answer 6

The evaporation of water from the surface of a plant

Question 7

What are the functions of the transpiration stream?

Answer 7

• Carry mineral ions to leaves for the synthesis of amino acid and chlorophyll
• To keep turgor pressure high in leaf cells (holding up leaves)
• Evaporation cools the leaves
• Supplies water for photosynthesis

Question 8

How to measure rate of transpiration experiment?

Answer 8

Using a potometer:
- Must be set up underwater (prevents any bubbles blocking the xylem)
- Cut the stem of a shoot
- Put shoot stem into the bung, grease the join with petroleum jelly (prevents water loss & air entry)
- Put bung into potometer
- Make sure tap is closed then take out of water
- Leave end of capillary out until bubble forms and put back in water

Question 9

How to measure rate of transpiration?

Answer 9

As distance the bubble travels in five minutes. Calculate mean.