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2.3 identify that Blackman and Mathgel hypothesised that photosynthesis was a two step process
identify that Blackman and Mathgel hypothesised that photosynthesis was a two-step process
Background information
In 1905, F.F. Blackman and G.L.C. Mathgel (also spelt Mathaei) cultivated plants under different carbon dioxide concentrations, light intensities and temperatures. They recorded the effects of these variables on the rate of photosynthesis. Blackman and Mathgel found that
- in conditions of excess carbon dioxide, the rate of photosynthesis increased with increasing light intensity. This was independent of temperature.
- in conditions of excess light, the rate of photosynthesis increased with increasing carbon dioxide concentration but that at high temperature the rate was greater than at low temperatures.
- Blackman and Mathgel concluded that photosynthesis was a two-stage process. The first stage was independent of carbon dioxide concentration and temperature and dependent only on light. The second stage was independent of light intensity and dependent on carbon dioxide concentration and temperature.
- In 1925, O. Warburg explained the results of Blackman as two classes of photosynthetic reaction: the light reaction and the dark reaction.