Nature is so grand that the structure of leaf which is a basic unit for converting absorbed CO2 and H2O into glucose is beyond full comprehension. The human beings break down every phenomena in nature into smaller manageable parts and understand it and then integrate the results. This is due to the evolution of our brain in a way that left hemisphere dominates. This hemisphere is the logical unit of the brain and analyses the problems by breaking them into modules. It is unable to see the things in the holistic manner. Only the artists use the right brain more and they see the scene as one single entity.
What do the plants do for the food? They use glucose to run the various processes in their lives. The inputs for making glucose include the CO2 and H2O and sunlight with the help of a special pigment called chlorophyll. It is this chemical which gives the leaves their green color. When the glucose is formed, the sunlight is stored in it in the form of chemical energy. Human beings take up the glucose as food. The enzyme which is called alpha amylase breaks down the starch (higher form of glucose) into CO2 and H2O again and releases the stored energy which is utilized by our bodies. This cycle goes on and on this cycle depends the existence of animals and plants. The end products of one’s actions are the starting materials for the other. This shows that we owe our existence to the Sun. Without the Sun life is impossible on the earth. Hindus and Zoroastrian people worship the Sun. When the Vedas and Zend Avesta was written, they may not be knowing the chemistry but even then intuitively they chose the Sun for worship.
The news has broken out from MIT about a professor who has been able to make a synthetic leaf. It does not synthesize the glucose but it breaks down the water into its individual components namely hydrogen and oxygen. The hydrogen so generated is a fuel, the cleanest of the fuels because when it is burned, it again forms the water vapors and releases energy. So the leaf can be more appropriately called a fuel cell. The water as such is a very stable molecule and it requires energy to break it into its components. Conventionally, electrolysis is used to break down the water and this requires energy. The professor must have used the metals which acts as catalysts and makes the reactions possible and lowers cost. He says that his leaf is 10 times more prolific then the natural leaf. But its working life is about 45 minutes.
Let us hope that energy problems are solved and our dependence on the exhaustible natural energy sources like fossil fuels decreases and these isolated inventions do not remain confined to the laboratory but become commercially viable. To read more about the leaf click this link.