Calvin

• Calvin’s study is also referred to as the ‘lollipop’ experiment as the apparatus he used was flattened from front to back to maximise light absorption 
• 1. Calvin added radioactive carbon dioxide to a suspension of the autotrophic protocista chlorella
• 2. After a short interval of time, the tap was opened and the chlorella was released into the hot methanol, killing it immediately and preventing any further reactions 
• 3. The chlorella was homogenised and the compounds present indentified by chromatography 
• 4. Calvin deducted that any compound present containing the 14CO2 must have been produced following the ‘fixing’ of the radioactive carbon dioxide in the light independent stage of photosynthesis 
• 5. He was able to identify glycerate phosphate as the first compound produced 
• 6. By slowing increasing the time intervals between adding the 14CO2 and kilometre the chlorella, he was able to identify the compounds produced at successive stages of the cycle