Expert: Walter Hintz - 5/29/2007

Question
QUESTION: Why is photosynthesis only about 1% efficient in converting the energy in sunlight onto stored organic molecules?  What happens to the rest of the energy?

ANSWER: Hi Deb
The Law of entropy states that when there is a change of energy from one form to another there is a loss of useful energy.  In photosynthesis light energy is changed to chemical energy.  The energy is not lost but is converted to heat.  Are you sure that the 1% figure is correct?  What is your source?

---------- FOLLOW-UP ----------

QUESTION: Our source is our AP biology teacher, but she will not answer this question for us.  She says that we can get any outside help that we need.  But she told us that the figuer was 1%.  We know where the other percentages go, but we don't know the reason why is is only 1% efficient.  

Answer
Hello again Deb
I asked about the 1% because it is not correct.  The efficiency of photosynthesis is around 5% not 1%.  I have also seen figures of up to 6.6%
 The answer I gave you as to why does  not really answer the question because we cannot really answer "why" questions.  The second Law  (entropy) is a natural Law.  It is a fact. The Universe is as it is because that is the way it works.  Why questions are evolutionary questions and that is how the Universe has evolved