Microbial Control & Identification
This process destroys all forms of microbial life, including vegetative cells, viruses, and bacterial endospores.
What is sterilization?
During this phase of the bacterial growth curve, cells adapt to new surroundings and synthesize enzymes without increasing total cell number.
What is the lag phase?
This initial cytosolic pathway breaks down one 6-carbon glucose molecule into two 3-carbon pyruvate molecules without requiring oxygen.
What is glycolysis?
Microorganisms that obtain their energy from light are phototrophs, while those that extract energy from chemical bonds are called this.
What are chemotrophs?
This universal energy currency of the cell consists of an adenine base, a ribose sugar, and three phosphate groups.
What is Adenosine Triphosphate (ATP)?
Unlike bactericidal agents that actively kill microbes, agents with this suffix merely inhibit or stop microbial growth temporarily
What is -static (or bacteriostatic)?
This dynamic model describes the plasma membrane as a viscous bilayer of lipids embedded with diverse functional proteins.
What is the Fluid Mosaic Model?
This molecule serves as the terminal electron acceptor in aerobic respiration, yielding the highest amount of ATP.
What is molecular oxygen (O_2)?
This physical control method uses steam under pressure at temperatures over 100°C to destroy all microbial life, including endospores.
What is autoclaving?
According to this fundamental thermodynamic law, energy cannot be created or destroyed, only transformed.
What is the First Law of Thermodynamics?
This physical control method uses non-ionizing radiation to form thymine dimers in microbial DNA, but has low penetration power and is primarily used for air and surface treatment.
What is ultraviolet (UV) radiation?
When a cell is placed in this type of solution, water flows out of the cell, causing the cytoplasm to shrink away from the cell wall.
What is a hypertonic solution (or plasmolysis)?
These organisms cannot survive in the presence of oxygen and rely exclusively on anaerobic pathways for energy.
What are obligate anaerobes?
These organisms harvest energy from chemical bonds and derive their carbon directly from inorganic carbon dioxide (CO_2).
What are chemoautotrophs?
Biological catalysts accelerate chemical reactions by lowering this specific energy barrier without altering Delta G.
What is activation energy (E_A)?
These two microbial structures represent the highest level of resistance to physical and chemical control measures.
What are bacterial endospores and prions?
This growth phase occurs when the rate of new cell division equals the rate of cell death as nutrients deplete and waste accumulates.
What is the stationary phase?
During oxidative phosphorylation, proton flow back into the matrix through this enzyme turns its rotor to synthesize ATP from ADP and P_i.
What is ATP Synthase?
In the nitrogen cycle, symbiotic root-nodule bacteria like Rhizobium perform this crucial process, converting N_2 gas into ammonia (NH_3).
What is nitrogen fixation?
This regulatory process occurs when the final product of a pathway allosterically inhibits an enzyme operating early in the chain to prevent resource waste.
What is feedback inhibition?
Laboratory technicians perform these four basic biochemical tests to detect specific metabolic end-products and rapidly identify unknown bacterial species.
What are sugar fermentation, oxidase, catalase, and gas production assays?
This quantitative laboratory technique measures living cells only by performing serial dilutions and counting colony-forming units on agar plates.
What is a viable plate count?
In the absence of an electron transport chain, fermentation generates only 2 net ATP via substrate-level phosphorylation primarily to regenerate this critical electron carrier.
What is NAD^+?
Chemolithotrophic bacteria like Thiobacillus act as "microbial miners" in sedimentary cycles by producing this acid to weather phosphate rocks into soluble PO_4^{3-}
What is sulfuric acid (H_2SO_4)?
Unlike competitive inhibitors that block the active site, this type of inhibitor binds to a separate site, altering the enzyme's overall protein shape.
What is a noncompetitive (or allosteric) inhibitor?