9. Biodeterioration, Biomediation, & Biotechnology Flashcards
What is biodeterioration, bioremediation, and biotechnology?
Biodeterioration is a change in the environment brought about by a particular prokaryotic metabolic process seen as a problem to be dealt with. Biotechnology is the very same metabolic process that may be exploited by humans and bioremediation is the use of biotechnology to mitigate environmental damage caused by humans.
Describe the production of nitrogen fertilizer.
Nitrogen fertilizer is made by reducing atmospheric nitrogen gas to ammonium. Large amounts of fossil fuels must be combusted.
Describe nitrate pollution.
Prokaryotes naturally oxidize ammonium from the decomposition of organic matter to nitrate. This process is called nitrification. Since nitrate is negatively charged, it is more easily lost in the rain and surface runoff. This results in eutrophication and explosive growth of phototrophs. This depletes oxygen in the water. Normally, the nitrate resulting from nitrification is ultimately converted to gaseous nitrogen gas in the soil which escapes to the atmosphere.
Describe nitrous oxide pollution.
Nitrous oxide results from the use of nitrate as a TEA by prokaryotes. Denitrification is a process that results in the conversion of solid nitrate to gaseous nitrogen gas or nitrous oxide which escapes to the atmosphere. If facultative aerobes are unable to get oxygen, they use nitrate as a TEA. Normally nitrous oxide is converted to nitrogen gas that use nitrous oxide as a TEA but there is too much nitrous oxide.
Describe Rhizobium legume symbiosis.
Plants need nitrogen but cannot use nitrogen gas as a nitrogen source. Bacteria also need nitrogen but nitrogen fixation is expensive in terms of energy. Plants have no problem accessing either energy or electrons. The plant assimilates carbon and makes sucrose. Some of the sugar is used to feed root cells and some are provided to the bacteria. The bacteria use the sugar as energy and electron source to make ATP and NADPH needed to fix nitrogen gas. The bacteria uses oxygen as a TEA.
Describe green nitrogen fertilizer.
In the first year, plant a crop of legumes and there is no need to apply nitrogen fertilizer. After harvesting them, plough the residual nitrogen rich plant shoots and roots into the soil to become the nitrogen fertilizer. From the first year to the second year, Micro organisms mineralize nitrogen and release it as ammonium waste into the soil. For the third year, plant a non-legume crop that uses the ammonium to grow.
How do you microbes and cows work?
Cows don’t possess the digestive enzyme cellulase. In the rumen, the cellulose is consumed and degraded by heterotrophic microbes. These microbes then give microbial biomass, proteins, and organic fatty acids to the cow.
Describe the methanogenic archaea in the cow.
In the rumen, these organisms use the waste products of other bacteria and produce methane as a waste product.
