Microbiology Final Exam Flashcards

Flashcards for reviewing key microbiology concepts, focusing on microscopy, cell structure, metabolism, growth, virology, immunology, pathogenicity, antimicrobial therapy, and biotechnology.

Brightfield Microscopy

A commonly used microscopy technique where the specimen is stained and appears dark against a bright background.

Darkfield Microscopy

A microscopy technique that enhances contrast for unstained, live organisms.

Phase-contrast Microscopy

Microscopy technique useful for observing internal structures in live cells.

Fluorescence Microscopy

Microscopy technique using UV light and fluorescent dyes to identify pathogens.

TEM (Transmission Electron Microscopy)

A type of electron microscopy used for viewing internal structures of cells.

SEM (Scanning Electron Microscopy)

A type of electron microscopy used for detailed surface images.

Prokaryotes

Cells without a nucleus or membrane-bound organelles, containing 70S ribosomes; includes bacteria and archaea.

Eukaryotes

Cells with a true nucleus, 80S ribosomes, and membrane-bound organelles; includes fungi, protozoa, algae, plants, and animals.

Gram Staining

A staining technique using crystal violet, iodine, alcohol, and safranin to differentiate bacteria based on cell wall structure.

Gram-positive Bacteria

Bacteria with a thick peptidoglycan layer that stains purple in Gram staining.

Gram-negative Bacteria

Bacteria with a thin peptidoglycan layer and an outer membrane that stains pink in Gram staining.

Acid-Fast Stain

A staining technique used for Mycobacterium species.

Endospore Stain

A staining technique to detect Bacillus and Clostridium spores.

Catabolism

The breakdown of molecules, releasing energy.

Anabolism

The building up of molecules, using energy.

Enzymes

Biological catalysts that speed up reactions by lowering activation energy.

Substrate-level Phosphorylation

Direct transfer of phosphate to generate ATP (e.g., glycolysis).

Oxidative Phosphorylation

ATP generation via the electron transport chain (ETC).

Photophosphorylation

Light-driven ATP generation in photosynthetic organisms.

Aerobic Respiration

Respiration that yields 38 ATP from one glucose molecule.

Anaerobic Respiration

Respiration using molecules other than O₂ (e.g., NO₃⁻, SO₄²⁻) as final electron acceptors.

Fermentation

Metabolic process that produces acids or alcohols, such as lactic acid in muscles or ethanol in yeast.

Psychrophiles

Microorganisms that thrive in cold temperatures.

Mesophiles

Microorganisms that thrive in moderate temperatures; many are human pathogens.

Thermophiles

Microorganisms that thrive in hot temperatures.

Acidophiles

Microorganisms that thrive in acidic environments.

Halophiles

Microorganisms that tolerate high salt concentrations.

Selective Media

Culture media that suppresses the growth of unwanted microbes.

Differential Media

Culture media that distinguishes between different species of microorganisms.

Enrichment Media

Culture media that favors the growth of rare microbes.

Virus Structure

Composed of genetic material (DNA or RNA), a capsid, an envelope (in some), and spikes.

Lytic Cycle

Replication cycle where the virus destroys the host cell.

Lysogenic Cycle

Replication cycle where viral DNA integrates into the host cell's genome.

Retroviruses

Viruses that use reverse transcriptase to convert RNA to DNA.

Prions

Infectious proteins that cause neurodegenerative diseases.

Innate Immunity

Non-specific immune defense mechanisms including skin, mucous membranes, phagocytes, fever, and inflammation.

Adaptive Immunity

Specific immune responses mediated by B cells (humoral) and T cells (cellular).

Humoral Immunity

Immune response mediated by B cells that produce antibodies.

Cellular Immunity

Immune response mediated by T cells (Helper CD4+ and Cytotoxic CD8+).

Inactivated Vaccine

A type of vaccine containing killed pathogens.

Attenuated Vaccine

A type of vaccine containing weakened pathogens.

Subunit Vaccine

A type of vaccine containing specific antigens of a pathogen.

mRNA vaccine

A type of vaccine that uses mRNA to instruct cells to produce antigens.

Vector-based vaccine

A type of vaccine that uses a modified virus to deliver antigens.

Herd Immunity

Indirect protection from infection when a large portion of the population is immune.

Virulence Factors

Traits of a pathogen that enhance its ability to cause disease.

Adhesins

Virulence factors that help pathogens attach to host cells.

Capsules

Virulence factors that inhibit phagocytosis.

Exotoxins

Secreted proteins with specific actions that damage the host.

Endotoxins

Lipid A component of Gram-negative bacteria that triggers fever and inflammation.

Siderophores

Molecules produced by pathogens to steal iron from the host.

Cell Wall Antibiotics

Antibiotics like penicillin and vancomycin that target bacterial cell wall synthesis.

Protein Synthesis Antibiotics

Antibiotics like tetracyclines and macrolides that inhibit bacterial protein synthesis.

DNA/RNA Antibiotics

Antibiotics like rifampin and fluoroquinolones that interfere with bacterial DNA/RNA synthesis.

β-lactamases

Enzymes that confer antibiotic resistance by inactivating β-lactam antibiotics.

Efflux Pumps

Bacterial resistance mechanism that pumps antibiotics out of the cell.

MIC (Minimum Inhibitory Concentration)

The lowest concentration of an antibiotic that inhibits bacterial growth.

Disk Diffusion (Kirby-Bauer)

A method to test antibiotic effectiveness by measuring zones of inhibition around antibiotic-impregnated disks.

Antivirals

Drugs that target viruses (e.g., acyclovir, oseltamivir, remdesivir).

Antifungals

Drugs that target fungi (e.g., amphotericin B, fluconazole).

Restriction Enzymes

Enzymes that cut DNA at specific sequences.

Ligase

Enzyme that joins DNA fragments together.

Vectors

Vehicles like plasmids or viruses used to carry foreign DNA into cells.

PCR (Polymerase Chain Reaction)

Technique used to amplify DNA.

Gel Electrophoresis

Technique used to separate DNA fragments by size.

CRISPR

Gene editing technology using Cas enzymes.