BIO121: Class Presentations
Class Structure and Presentation Overview
- Class Format:
- Instructor will not engage in Q&A during presentations.
- Stand-up signal indicates time is short (about 1 minute). - Group Presentations:
- Teams will present their research topics sequentially.
Algal Growth Study on Nutrients in Freshwater Ecosystems
- Research Focus: Effects of nitrogen and phosphorus on algae growth in aquatic ecosystems.
- Research Question: How do increasing concentrations of nitrogen and phosphorus affect algae growth in freshwater ecosystems?
- Nutrient Importance:
- Nitrogen and phosphorus are limiting nutrients essential for plant and algae growth.
- These nutrients are crucial for cellular respiration and photosynthesis in aquatic ecosystems.
- Phosphorus typically acts as a more critical limiting nutrient than nitrogen. - Sources of Nutrients:
- Human activities, including agriculture (fertilizers), urban runoff, and wastewater discharge
- These lead to nutrient excess, resulting in eutrophication. - Consequences of Nutrient Overload:
- Harmful algal blooms reduce water clarity and deplete oxygen levels, leading to hypoxia.
- Negative impacts on aquatic life (e.g., fish deaths due to oxygen depletion).
- Certain algae like cyanobacteria produce toxins that threaten both animal and human health.
Experimental Design
- Significance of Study:
- Freshwater ecosystems are vital for drinking water and biodiversity.
- Excess nutrients can shift ecosystems toward being algae-dominated. - Hypotheses and Expectations:
- Expected positive correlation between nutrient levels and algal growth.
- Nutrient thresholds for phosphorus in lakes and streams are very low (e.g., 0.005 mg/L for lakes).
Methodology
- Experimental Setup:
- Conduct laboratory experiments with different nutrient concentrations: low, medium, high, and a control group.
- Measurement Techniques:
- Use spectrophotometry (680 nm) to measure optical density, indicating algal biomass growth. - Data Collection and Analysis:
- Regular optical density measurements will be taken during a 7-day growth period.
- Calculate averages and standard deviations for quantifying algal growth.
- Graph results showing time versus optical density to illustrate growth rates.
Expected Results
- Graph Interpretation:
- A positive correlation between nutrient levels and algal growth is expected; higher nutrients lead to greater optical density.
- If no growth difference noted, other factors may become more significant. - Biological Implications:
- Biodiversity costs from harmful blooms and potential ecosystem collapse should be addressed in management policies.
Kelp and Ocean Acidification
- Research Question: How can giant kelp mitigate ocean acidification?
- Ocean Acidification Causes:
- Rising global temperatures and elevated atmospheric carbon dioxide.
- Particularly affects organisms with calcium carbonate shells, such as mollusks. - Role of Giant Kelp:
- Kelp provides habitat and produces oxygen via photosynthesis (70% of global oxygen production).
- It also sequesters carbon; when kelp dies, carbon can be trapped in ocean sediment.
Experimental Design
- Hypothesis:
- Kelp in acidic waters will promote healthier growth and increase pH levels. - Study Variables:
- Compare biomass and oxygen production of kelp in two pH levels (7.9 and 8.1).
- Monitor growth metrics over several weeks to determine effectiveness against acidification.
Expected Results
- Outcomes:
- Anticipated increases in growth rates and overall health indices of kelp in acidic conditions.
- Results may demonstrate how enhancing kelp populations could benefit around carbon sequestration and biodiversity. - Broader Impacts:
- Applications in biotechnology (biofuels, bioplastics) and environmental management.
Gender Segregated Housing and Microbial Islands
- Research Question: Does gender-segregated housing influence microbial diversity and pathogen prevalence?
- Microbial Environments:
- Dormitories are considered built environments rich in bacteria due to high human contact.
- Focus on gram-negative bacteria, which are often resistant and harmful. - Significance of Study:
- Limited research in gender-segregated living areas could provide insights into hygiene and sanitation practices.
Experimental Design
- Hypotheses:
- Higher concentrations of gram-negative bacteria will be found in male dorms compared to female dorms. - Methodology:
- Swabbing high-touch surfaces in male and female dormitories for bacterial samples using sterile techniques.
- Utilize metagenomic analysis to identify bacterial species present in each sample.
Expected Results
- Outcomes:
- Anticipated to find higher CFUs and greater prevalence of harmful bacteria in male dorms versus female dorms.
Genetic Modifications for Endangered Species
- Research Question: Can genetic modification of food supplies enhance the population of endangered species like the black rhino?
- Genetically Modified Organisms (GMOs):
- Improve agricultural yields and consumer appeal; objective is to apply these tactics to support endangered species.
Experimental Design
- Hypothesized Outcomes:
- Enhanced availability of genetically modified food sources should improve black rhino populations.
Methodology
- Approach:
- Identify natural food sources and selectively modify them for better yield.
- Monitor population metrics over time to see if improved nutrition leads to population growth.
Mutation Rates and Antibiotic Resistance in E. Coli
- Research Question: How do mutation rates influence the evolution of antibiotic resistance in E. Coli?
- E. Coli Strains:
- Wild-type E. coli demonstrates standard mutation rates while hypermutator strains display accelerated evolution under antibiotic exposure.
Experimental Design
- Hypothesis:
- Higher mutation rates will lead to faster antibiotic resistance evolution.
Methodology
- Experimental Setup:
- Utilize controlled lab experiments to compare the growth of wild-type versus mutator E. coli under antibiotic exposure.
Expected Results
- Outcomes:
- Expect to see higher rates of resistance in mutator strains within shorter timeframes compared to wild-type strains.
H2AX as a Biological Indicator in Cancer Chemotherapy Trials
- Research Question: Is gamma H2AX an accurate biological indicator of chemotherapy efficacy?
- H2AX Role:
- A histone protein that phosphorylates to indicate DNA damage through chemotherapy treatments.
Methodology
- Experimental Design:
- Blood samples from leukemia patients will be assessed pre- and post-chemotherapy treatment for DNA damage.
Expected Outcomes
- Findings:
- Anticipate a significant increase in gamma H2AX levels post-treatment indicating effective DNA damage and repair mechanisms.
UV Radiation and Microgravity Effects on Plant Photosynthesis
- Research Question: How do elevated UV radiation and microgravity impact kale oxygen production?
- Microgravity Effects:
- Alterations in root systems and nutrient transport can affect overall plant health and photosynthesis efficiency.
Experimental Design
- Hypothesis:
- Increased UV radiation in microgravity decreases photosynthetic efficacy, reflected in decreased oxygen production.
Methodology
- Study Setup:
- Simulated microgravity conditions will be employed to measure kale growth and oxygen output under UV exposure.
Expected Outcomes
- Findings:
- Insight into plant stress responses and implications for sustainable life-support systems in long-duration space missions.
Conclusion
- The class session concluded with a variety of innovative research presentations covering critical topics in environmental science, ecology, and health.
- Insights from these presentations may contribute to broader discussions on conservation, public health, and biotechnological innovations.