In the Beginning was Information

This process synthesises complex, energy-rich substances. What usuallyhappens in oxidation/reduction reactions is that a strong oxidising agentoxidises a reducing substance, but photosynthesis is exceptional in thisrespect. It employs a weak oxidising substance (CO 2 ) to oxidise a weakreducing agent (H 2 O) to produce a strong oxidising substance (O 2 ) and astrong reducing compound (carbohydrate). This process requires the inputof external energy, namely sunlight. Such a process can only occur in thepresence of a substance which can absorb light quanta, transfer the energyto other molecules, and then revert to its initial state where it can againabsorb quanta of light. Chlorophyll performs this complex function. Thereare five types of chlorophyll (a, b, c, d, and f) which differ only slightly inchemical structure. Occurring in “higher” plants and in green algae, types aand b are the most important. The chemical equation for photosynthesis is:6 CO 2 + 6 H 2 O + light energy C 6 H 12 O 6 + 6 O 2 (1)In this process glucose is synthesised from CO 2 and H 2 O by employingthe energy of sunlight. The capture of light energy and its conversion tochemical energy is only one part of the process. These initial reactions arecalled photochemical reactions, and all subsequent reactions where chemicalenergy is utilised for the synthesis of glucose do not require lightenergy; they are thus known as dark or umbral reactions.The ability to absorb light varies very strongly from one substance to another.Water absorbs very little light and thus appears to be colourless. Thecolour of a substance depends on the absorption (and reflection) of certainwavelengths of light. When the degree of absorption is plotted against wavelength, we obtain an absorption spectrum. Chlorophyll only absorbs bluelight (wavelength 400 to 450 nm) and red light (640 – 660 nm), so that thereflected light is green. The active spectrum of a process refers to its efficiencyin relation to its wavelength. It is therefore noteworthy that theabsorption spectrum of chlorophyll closely corresponds to the active spectrumof photosynthesis. This indicates that a finely tuned concept underliesthis vital process and an efficiency calculation supports the view thata brilliant Mind is involved.The efficiency of photosynthesis: According to equation (1) 1 mol 26 ofFor one mol of CO 2 , this is then 478.7 kJ. Since energy losses accompany26 One mol (1 mol) is the quantity of a substance in grams corresponding to its molecularweight (also known as relative molecular mass). The molecular weight of acompound is a dimensionless ratio obtained by adding the atomic weights of theconstituent atoms. For example: The molecular weight of CO 2 = 12 + 2 x 16 = 44, sothat 1 mol of CO 2 is 44 grams. It is noteworthy that the number of molecules in onemol of any substance is equal, namely (6.0221367 ± 0.0000036) x 10 23 . This numberis known as the Avogadro number N A , which is a fundamental physical constant.231