Marine Microbiology Questions and Concepts Study

Marine Microbiology and Bacterial Ecology Study Questions

This document compiles a comprehensive set of study questions and theoretical concepts focusing on marine microbiology, bacterial ecology, analytical methodologies, and microbial physiology in aquatic environments.

Bacterioplankton and Marine Biomass

• Classify marine bacteria according to their size and plankton distribution.
• Cita 3 advantages of the Bottle use for water samples at deep levels.
• What is the composition of synthetic sea water?
• Why is fluorescence microscopy used?
• Cite 3 environmental conditions determining biomes and 3 factors affecting marine bacterial activity.
• What is marine snow?
• Illustrate through drawings the photochemical apparatus of cyanobacteria and photosynthetic pigments.
• Cite 2 indirect methods for counting marine bacteria.
• Explain the fundamental principles of the previously cited methods.
• Explain the situation of the domains within the phylogenetic tree proposed by Carl Woese.
• Describe the pigment composition of Prochlorococcus.
• Explain how anaerobic and purple non-sulfur bacteria survive in darkness.
• Explain the habitat where red and green bacteria coexist.
• Situate phylogenetically the different groups of photosynthetic bacteria.
• Explain the technique based on formazan formation for studying the viable but non-culturable (VBNC) state.
• What is the most accepted theory regarding the viable but non-culturable state, and what evidence supports it?
• What cellular size and morphological changes accompany the viable but non-culturable state?
• Cite marine habitats where Thermotoga can be found.
• Explain spirochete morphology with a drawing.
• Situate phylogenetically Pseudomonads and cite two representatives in water samples.
• Name and differentiate the functions of appendages and prosthecae.
• Explain the reproductive cycle of Hyphomacterium.

Chemolithotrophs, Symbiosis, and Specific Groups

• Cite 3 genera of sulfur-oxidizing chemolithotrophs.
• Explain the symbiosis between Beggiatoa and rice roots under specific environmental conditions.
• Explain why iron is scarce in marine bacterial environments.
• Cite 5 characteristics of the genus Vibrio.
• How would you explain gas production in enterobacteria?
• Where would you find marine methylotrophic bacteria and why?
• What is the ecological role of Bdellovibrio in the marine environment?
• Explain sulfur-reducing bacteria in the marine trophic chain.
• Explain how the generation system of green and purple sulfur-reducing bacteria works.
• Explain why oxygenic heterotrophic bacteria develop in specific marine environments.
• Specify the characteristics of Nitrobacter.
• Explain the culturability of luminescent bacteria recovering organ luminescence.
• Fundament of the fluorescent in situ hybridization (FISH) technique.
• Enumerate 2 advantages of the laser scanning confocal microscope.
• What is the green fluorescent protein (GFP) used for?
• Why is the biomass relation correlated with phytoplankton producers in the water column?
• Explain through a diagram the role of marine bacteria in organic matter cycles.
• Explain aerobic heterotrophic bacteria development.
• Which Gram-positive bacteria are most frequent in water samples?
• Important metabolic characteristics of Sphingopyxis.
• Development of psychrophilic bacteria enrichment assays.
• Purpose of using enrichment techniques.
• Use of the most probable number (MPN) technique.
• What is the maximum number of cells per tube in a dilution series showing growth in MPN?

Winogradsky Columns and Nutrient Cycles

• Why does the Winogradsky column not establish a sequential depth graduation for phosphorus?
• Fundamentals of nitrifying bacteria selection.
• How would you manifest the presence of sulfur-reducing bacteria?
• And ammonifying bacteria?
• Fundamentals of the isolation of luminescent bacteria.
• Define Neuston.
• Cite 3 direct methods used to calculate bacterial biomass.
• Explain the advantages of one of these methods.
• Use of the Winogradsky column.
• Advantages of using fluorescent quantification for marine bacterial biomes.
• Size of bacterioplankton.
• Optimal incubation temperature for psychrophilic bacteria.
• Characteristics of TCBS agar.
• Definition of marine bacteria regarding nutrient levels: oligotrophic and barophilic.
• Is bile esculin a differential, selective, or enrichment medium?
• Why does the pycnocline concentrate bacterial populations?
• Function of heterotrophic bacteria in the microbial loop.

Advanced Molecular Techniques and VBNC State

• What is the GFP staining method and how do fluorescent dyes differ from DAPI and fluorescent antibodies?
• Differences between streak plate and pour plate isolation methods regarding depth and colonies.
• Which cellular part is the target of fluorescent probes?
• What additional information does FISH provide alongside TWI?
• Ideal molecular technique for studying bacterial diversity in natural samples.
• What information is provided by analyzing mRNA using specific techniques?
• What is the purpose of PCR primers?
• Why is a denaturing agent used in electrophoresis?
• Cite 2 components forming complex media and 2 defining a defined heterotrophic medium.
• How do you sterilize 1 liter of a thermolabile culture medium?
• How do you determine sample size after plate counting?
• How is particle disaggregation performed in water samples?
• Limitations of sampling the air-water interface.
• Proposal regarding Woese's phylogenetic tree of current living beings.
• Metabolic characteristics determining mixotrophy.
• 3 environmental parameters determining marine bacterial growth in our latitudes.
• Characteristics regarding the size of Sphingomonas.
• Why is the maximum primary production displaced relative to the phytoplankton maximum?
• 1 example of deep-sea areas associated with high density.
• Role of aquatic viruses in environmental settings.
• Role of ppGpp in ultramicrobacteria formation.
• Difference between Photobacterium and nutrition requirements of Sphinges.
• Define the viable but non-culturable (VBNC) state.
• Is it a degenerative process?
• Cite 3 data points supporting the cellular cycle part.
• Explain what cellular activity is measured using the Kogure technique.
• 3 factors describing and determining the VBNC state in bacteria.
• Cellular characteristics affected by the VBNC state.
• Main difference between reproductive divisions and adaptation media to oligotrophy in the VBNC state.
• Role of cytokines in the VBNC state.
• Role of the VBNC state in Patagonian organisms.
• Do pathogenic bacteria conserve virulence markers in the VBNC state?
• How do heterotrophic and autotrophic organisms couple in oligotrophic environments?
• Role of heterotrophs in microbial biofilms.
• Composition of cyanobacterial antenna pigments.
• Pigment differences in Prochlorococcus marinus.
• How limits the sulfur-driven activity of green and purple bacteria their place in the water column?
• How is emission maximized in purple sulfur-reducing bacteria?
• Who acts as an electron donor in these bacteria?