Student Sheet 3 - Investigating the behaviour of leaf discs

This provides a fun way for students to get hands-on when investigating photosynthesis.

Students punch out small discs from leaves, and float them in a syringe of sodium hydrogen carbonate solution. Once gas is evolved by photosynthesis, the leaf discs rise and fall.

Students can compare the rate of photosynthesis in sun and shade plants and at different light intensities, amongst many other factors.