IGCSE Biology : Gas Exchange Topic Materials
Leaves are essential for photosynthesis, absorbing sunlight energy.
Chloroplasts in cells contain chlorophyll, which absorbs sunlight for photosynthesis.
Photosynthesis equation: sunlight + carbon dioxide + water → oxygen + glucose.
Leaves are flat and thin with a large surface area to maximize sunlight and carbon dioxide absorption.
Vessels like xylem and phloem transport water, minerals, and glucose within the plant.
Guard cells regulate gas exchange through stomata, opening and closing as needed.
Temperature: Increased temperature initially boosts photosynthesis, but enzyme denaturation beyond a certain point decreases the rate.
Light intensity: Higher light intensity increases photosynthesis rate, inversely proportional to the square of the distance from the source.
Carbon dioxide concentration: Higher carbon dioxide levels enhance the reaction rate.
Using water plants like Elodea to observe oxygen bubbles released during photosynthesis.
Experimenting with light intensity by measuring oxygen evolution at varying distances from a lamp.
Testing carbon dioxide effects by altering sodium bicarbonate concentrations in the water.
Starch production indicates photosynthesis occurrence.
A leaf covered with oil and exposed to light will show starch presence through a color change with iodine solution.
Variegated leaves demonstrate starch production only in green areas containing chlorophyll.
Stomata are small openings on leaf undersides regulating water loss and gas exchange.
They facilitate the exit
Leaves are essential for photosynthesis, absorbing sunlight energy.
Chloroplasts in cells contain chlorophyll, which absorbs sunlight for photosynthesis.
Photosynthesis equation: sunlight + carbon dioxide + water → oxygen + glucose.
Leaves are flat and thin with a large surface area to maximize sunlight and carbon dioxide absorption.
Vessels like xylem and phloem transport water, minerals, and glucose within the plant.
Guard cells regulate gas exchange through stomata, opening and closing as needed.
Temperature: Increased temperature initially boosts photosynthesis, but enzyme denaturation beyond a certain point decreases the rate.
Light intensity: Higher light intensity increases photosynthesis rate, inversely proportional to the square of the distance from the source.
Carbon dioxide concentration: Higher carbon dioxide levels enhance the reaction rate.
Using water plants like Elodea to observe oxygen bubbles released during photosynthesis.
Experimenting with light intensity by measuring oxygen evolution at varying distances from a lamp.
Testing carbon dioxide effects by altering sodium bicarbonate concentrations in the water.
Starch production indicates photosynthesis occurrence.
A leaf covered with oil and exposed to light will show starch presence through a color change with iodine solution.
Variegated leaves demonstrate starch production only in green areas containing chlorophyll.
Stomata are small openings on leaf undersides regulating water loss and gas exchange.
They facilitate the exit
