CHE 309 Assignment Questions with Solutions 2014

Assignment Questions Algae’s Clock BCG Vaccines BCG Vaccines are less important in Canada than in South Africa because of the low risk of contracting Tuberculosis in Canada. While it is not commonly used in Canada, the BCG vaccine can be considered for at risk infants and some native communities. Bioventing/Biosparging For the fermentation of indigenous hydrocarbon degrading microorganisms in soil to be possible there must be a source of energy, a source of carbon, nutrients (Nitrogen, Sulfur, Potassium, Calcium), soil moisture and available oxygen. Drugs from Algae Two advantages of using Chlamydomonas reinhardtii for expressing therapeutic proteins is its rapid reproduction and its chloroplasts ability to properly fold complex proteins. Edible Vaccines (Problem with File) Human Osteoblasts The two cells involved in making the bone matrix is the Osteoblast and Osteoclast/Osteocyte. The Osteoblast synthesize and mineralize bone while the Osteoclast/Osteocyte breaks down the bone matrix. Hydrogen Fuel Two of the conditions for the production of dihydrogen is the purging of the ultrapure nitrogen, as well as keeping the reactor temperature at 50C. Without purging the product dihydrogen would be contaminated by dinitrogen. If the temperature of the reactor were to be raised or lowered it would affect the enzyme activity , limiting dihydrogen production. Methane The four steps involved in anaerobic digestion are hydrolysis, acidogenesis, acetogenesis and methanogenesis. The process starts by hydrolysis using Cellulomonas bacteria which breakdown organic material into a simpler state. The simple organic material now undergo acidogenesis by Saccharomyces cerevisiae into volatile fatty acids (VFA). During acetogenesis Syntrophomonas wolfei converts the VFA into acetate, CO2 and hydrogen which are consumed by Methanococcus microorganisms which convert them into biogas, mainly methane. Nanocapsules Two attributes of the nanocapsusles that make them a successful form of cancer treatment is that they can deliver the medicine directly into the cells and are specific enough to only affect cancerous cells. Phytoremediation Hyperaccumulators are plants that can accumulate a large amount of heavy metals, in this case Arsenic, compared to other plants. An example of an Arsenic hyperaccumulator is Pteris vittata. Purple Bacteria Rhizofiltration Terrestrial plants are preferred over aquatic plants for rhizofiltration because the root systems of terrestrial plants tend to be long, faster-growing and more fibourous which helps improve root surface area. Stem Cells The difference between embryonic stem cells and adult stem cells is their ability to differentiate. Embryonic stem cells are pluripotent while the adult stem cell is limited in its ability to differentiate. Tissue Eng For structural tissues, the CTO states that they must retain its ability to be reconstructed, repaired or replaced. Conversely, cells and non-structural tissues must retain their original biological characteristics for proper functioning. ASSIGNMENT: What are hyperaccumulators? Provide an Example. Example: Pteris Vittata A hyperaccumulator is a plant that absorbs toxins, such as heavy metals, to a greater concentration than that in the soil in which it is growing. Compared to non- hyperaccumulating species, hyperaccumulator roots extract the metal from the soil at a higher rate, transfer it more quickly to their shoots, and store large amounts in leaves and roots. Briefly explain the process of anaerobic digestion and describe the four steps involved. Include an example of a microorganism involved for each step. Answer: Anaerobic digestion is a natural process where a variety of natural organisms biodegrade carbon rich matter in low oxygen environments. Hydrolysis is the first step and involves the breakdown of complex organic molecules to simple soluble monomers. Cellulomonas bacteria are involved in hydrolysis.  The second step, acidogenesis converts simple organic matter to volatile fatty acids. Saccharomyces cerevisiae is involved in this step. Acetogenesis is the third step and is the conversion of volatile fatty acids to acetate, CO2, and hydrogen. Syntrophomonas wolfei is involved in this conversion. The final step, methanogenesis, involves methanococcus microorganisms which convert acetate, CO2, and hydrogen to biogas, consisting of mainly methane. Rhizofiltration is used by planting Terrestrial plants in contaminated water, why is it better to use these terrestrial plants when there are already water plants present? Terrestrial plants have a longer, more fibrous root system that is covered with root hairs, this creates greater surface aria than the smaller, slow growing roots of the Aquatic plants. Aquatic plants can also cause problems once the contaminant has been collected because the roots have a higher water content they are more complicated to dry, and dispose of. Q: What are the two cells that work coherently to create the bone matrix (structure)? Describe their functions. A: The two cells that work coherently to create the bone matrix is the osteoclast and the osteoblast. The osteoclast is a type of bone cell that resorbs (dissolves/assimilates) the bone tissue. This is critical in the maintenance and repair of bones in the skeletal structure of mammals. Osteoblasts on the other hand are cells in single nuclei that synthesize bone. The osteoblast cells must be organized into groups (single cells cannot do this) in order to carry out the synthesis. Therefore osteoclasts and osteoblasts are instrumental in the creation of bone in mammals. What is the difference between a positive feedback loop and a negative feedback loop? Please use a biological process within an organism to explain the difference. A negative feedback loop refers to the reaction that slows down a process, whereas a positive feedback loop tends to accelerate it. For example, the rhythms of phosporylation in cyanobacteria relies on the time keeping system of circadian clocks. Phosphorylation is the addition of a phosphate group to a protein or any other organic molecule. The activation of enzymes relies on the addition of phosphate group. In this case, phosporylation is a positive feedback loop and dephosporylation is a negative feedback loop. Assignment Question: What are the requirements for the fermentation of indigenous hydrocarbon degrading microorganisms in soil? Answer: 1) Source of energy 2) Carbon 3) Nutrients 4) Moisture 5) Oxygen Assignment Question: Explain one advantage of using purple bacteria in industrial applications. Answer: Purple bacteria are abundant and easily found in nature. It is photosynthetic bacteria and therefore its application to products requires minimal intermediate modification steps. Assignment Question: What is Bio-encapsulation? Describe its importance in Edible vaccine. Answer: Bio-encapsulation is a preservation method commonly utilized for food, bioceuticals, and medicine. The molecules or materials of interest are surrounded by a specialized coating which allows for extended shelf life, controlled release, and increased effectiveness. In edible vaccine it is actually the protective cell wall. Since the vaccine is a modified protein inside the cell, its cell wall protects the antigens against attack by enzymes, gastric and intestinal secretions. The wall eventually breaks down in intestines where it is absorbed. Q: List 2 main process conditions for the production of dihydrogen. Give specific examples of what could occur if these conditions are not met. A: In the process of dihydrogen, there are 3 main process conditions that must be met and maintained. First, the bioreactor must be kept at a temperature of 50 degrees Celsius, so that the enzymes work efficiently and do not denature. Second, a constant stream of ultra-pure nitrogen must be purged through the bioreactor. Lastly, to keep the working volume constant, the carrier gas must be humidified and controlling condensation using a condenser kept at 18 degrees Celsius. If the bioreactor temperature fluctuates too much from 50 degrees Celsius (in excess of 5 degrees Celsius), this would negatively affect enzyme activity. The specific shape of each enzyme would be altered, thus being detrimental to enzyme function. The constant purge of ultrapure nitrogen takes away the oxygen in the bioreactor, which then initiates the reaction to produce H2, and using the condenser at 18 degrees Celsius ensures that the working volume of the reactor remains constant at 1 mL.