Generally, a precursor is defined as a compound that participates in a chemical reaction to release another compound. More specifically, in biochemistry, the term is used to refer to a chemical compound that precedes another in a metabolic pathway. Precursor molecules are thus involved in biology as precursor metabolites. In the catabolic pathway, raw materials are broken down into smaller units called precursor molecules which are needed in synthesize of building blocks such as amino acids, fatty acids, and monosaccharide. In anabolic pathways, the released precursor molecules in the catabolic reaction are utilized to build up macromolecules.
Question two
The micro-photosynthetic power cell is a newly emerging technology for harvesting energy using light or in more detailed term photosynthesis together with carbohydrate metabolism. This reaction takes place in the dark, also known as respiration. From the review of the article, therefore, the technology is believed to harness photosynthetic power from the green-blue algae (World Scientific, 2015). The key concept is that in blue-green algae, the photosynthetic energy cells are composed of proton, anode, and cathode exchange membrane (World Scientific, 2015). The anode part of the system is comprised of cyanobacteria, capable of releasing electrons to the electrode’s surface through a redox reaction which takes place at the cathode. To extract electrons from the process, an external load is integrated into the system.
Micro-photosynthetic power cell can be used as a possible source of energy, considering that it not only uses algae as well as solar power, but it also releases energy in light and dark conditions. The form of power harvesting can be regarded as clean energy and hence green technology in that it utilizes only algae and sunlight to release energy. It is a technology capable of deriving energy from the sun, and therefore it is eco-friendly and safe for human life. The connection of this technology to microbiology and more specifically in this chapter is that photosynthetic microorganisms are used in the anode chamber to release electrons. The system uses the technique of microbial fuel cells to generate electricity in dark and light conditions using photosynthesis as its source of electrons. In light condition, electrons, as well as protons, are utilized to release electricity in water-splitting photosynthetic reaction (energy harvesting). In dark condition, protons, as well as electrons generated from metabolic reactions of sugars that were released during the photosynthesis process (energy conversion), is used as now the source of the electricity. More specifically, the system is based on aerobic and anaerobic reactions to produce electricity.