In photosynthesis, which chemicals are needed for the light-dependent reaction? Tick (✔) one box - AQA - A-Level Biology - Question 7 - 2019 - Paper 1

During photoionisation, chlorophyll absorbs light energy, which excites electrons within the chlorophyll molecule. As a result, these electrons are lost from the chlorophyll, making it positively charged. This loss of electrons initiates a series of reactions in the photosynthetic pathway.

The student used a pencil to mark the origin because ink may dissolve and mix with the pigments, potentially leading to inaccuracies in the results.

The student placed the chromatography paper in a solvent. The solvent ascended the paper by capillary action, carrying the pigments along with it. Different pigments traveled different distances based on their solubility in the solvent and their affinity for the paper, resulting in separation.