Light And Water Availability Controlling The Opening And Closing Of Cells

Question 1

Explain how water availability control the opening and closing of cells

Answer 1

• stomata are closed where there isn’t much water in guard cells
• when water availability increases, the thin walls bulge out
• water moves in via osmosis

Question 2

Explain how light availability control the opening and closing of cells

Answer 2

• stomata usually open during the day, due to light intensity
• as more stomata require to allow CO2 to move in through photosynthesis
• in order for photosynthesis to release oxygen and closes during the night as light decreases
• although some plants close the stomata to prevent water loss/ save ore water