1. Describe a nichea. Populations and guilds of microorganisms live in these microenvironments where factors such as nutrients, antagonism by other organisms, pH, temperature, and other condition form a niche2. Know the biotic and abiotic factors that affect microbial growtha. Biotici. Symbiosesii. Antagonismiii. Synthrophyiv. Guildsv. Competitionvi. Predationvii. parasitismb. Abiotic i. pHii. Nutrientsiii. temperature3. Understand how nutrient availability affects microbial growth rates a. Most microbes live in a feast or famine existenceb. Rare opportunities of short term nutrient input are separated by long periodsof imposed dormancyc. IN nature doubling times of months or years are common 4. Know how microbes benefit by living in biofilms a. Protection from predatorsb. Better nutrient availabilityc. Physical protection from changing environmental conditions5. Be able to describe the process of biofilm development and what microbial mats area. Stepsi. Attachment- Adhesion of few motile cells to a suitable solid surfaceii. Colonization- Intercellular communication growth, and polysaccharideformationiii. Development- More growth and polysaccharideiv. Active Dispersal- Triggered by environmental factors such as nutrient availability b. Biofolms first develop as cell monolayers, then multilayers and eventually mature complex assemblages of cell aggregates, interstitial pores and conduitchannels. c. Microbial Matsi. In aquatic habitats, biofilms can form into multiple layered communities. 6. Describe how biofilm from a bacterial pathogen affects patients with cystic fibrosisa. Pseudomonas aeruginosa uses quorum sensing to establish lung infections in patients with cystic fibrosisb. Major cause of pneumonia in CF patientsc. Growth of bacterium is dependent on quorum sensing and biofilm formation.7. Explain why microbes within a biofilm have increased resistance to antibioticsa. The penetration barrier that make that blocks out changing environmental factors8. Understand the role of microbes in the distribution of oxygen in summer-stratified lakes a. Microbes use up O2 anerobic respiration9. Describe how oxygen, bacteria, and organics change downstream of a pollution entry point in a river a. Rise in bacterial activityb. Resulting decreased in dissolved O2c. As organic food is consumed bacteria levels decreased. Photosynthetic algae and cyanobacteria growth increases O210. Define what biochemical oxygen demand is, and what BOD is used to measure a. The amount of biologically usable organic carbon in water is indirectly measured by its BODb. Used to measure the portion of total carbon that can be oxidized by microorganism in a 5 day period under standard conditions 11. Describe the microscopic prokaryotic and eukaryotic primary producers in the open ocean a. Prokaryotic i. Cyanobacteria: oxygenic photosynthesis bacteriab. Eukaryotici. Unicellular alga12. Know the unique features of habitats and the types of microbial communities around deep ocean thermal vents a. Warmer habitats near vents provide environment for microbes to growb. No sunlight penetrates to these regionsc. Entire living ecosystem based on chemical energy instead of solar energyd. Typically found 1,000-4,000 meters below surfacee. Water contained dissolved minerals inside the vents can be up to 400ºCi. Surrounding water 5-50ºCii. Excellent habitat for microbial
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