IGCSE Biology : Gas Exchange Topic Materials

Leaves

Essential organs for photosynthesis, absorbing sunlight energy.

Chloroplasts

Contain chlorophyll for absorbing sunlight in photosynthesis.

Photosynthesis Equation

sunlight + carbon dioxide + water → oxygen + glucose.

Adaptations of Leaves

Flat and thin with large surface area for sunlight and carbon dioxide absorption.

Vessels (xylem and phloem)

Transport water, minerals, and glucose within plants.

Guard Cells

Regulate gas exchange through stomata, opening and closing as needed.

Factors Affecting Photosynthesis

Temperature, light intensity, and carbon dioxide concentration.

Practical Investigations in Photosynthesis

Using Elodea for observing oxygen bubbles, experimenting with light intensity, and testing carbon dioxide effects.

Starch Production

Indicates photosynthesis occurrence, tested with iodine solution on leaves.

Stomata Function

Small openings on leaf undersides regulating water loss and gas exchange.