Thursday, 25 April 2013

5.2 understand the effects on crop yield of increased carbon dioxide and increased temperature in glasshouses

Glass houses and polythene tunnels increase the heat in the environment that crops are growing in. Reactions happen faster when there is more heat, for example photosynthesis. Given photosynthesis produces energy that the plant needs to grow, if there is more heat there is more growth and so higher yield.

Carbon dioxide is a reactant in photosynthesis. If there is a more than enough carbon dioxide, then every plant will be able to photosynthesise as best as it can. The more photosynthesis the more glucose, the more glucose the more energy, the more energy the more growth. Hence crop yield is increased.


  1. Is it so that if the temperature are very high then the rate of photosynthesis may decrease as well?

    1. Yes, good point, if the temperature became too high then the plant would not be able to function properly (enzymes involved in reactions would denature).

  2. This is unbelievably helpful, thanks so much!

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