Microbiology

Flashcards for a microbiology 200-level currency exam

Prokaryotic Cells

Cells that lack a nucleus and membrane-bound organelles.

Eukaryotic Cells

Cells that have a nucleus and membrane-bound organelles.

Endosymbiotic Theory

The theory that mitochondria and chloroplasts originated from free-living bacteria engulfed by an ancestral eukaryotic cell.

Bacterial Cell Wall

Provides structure, protection, and prevents osmotic lysis.

Gram-positive Bacteria

Bacteria with a thick peptidoglycan layer that stain purple.

Gram-negative Bacteria

Bacteria with a thin peptidoglycan layer, an outer membrane, and stain pink.

Fimbriae

Structures that help bacteria attach to surfaces.

Pili

Appendages used by bacteria for conjugation (DNA transfer).

Genotype

The genetic makeup of an organism.

Phenotype

The observable characteristics of an organism.

Transposons

'Jumping genes' that can move between DNA molecules.

Operons

Clusters of genes regulated together that control bacterial gene expression.

Enveloped Viruses

Viruses that have a lipid membrane.

Non-enveloped Viruses

Viruses that lack a lipid membrane and are more resistant to environmental factors.

Viral Replication Steps

Attachment, penetration, biosynthesis, assembly, release.

Reverse Transcriptase

An enzyme that converts viral RNA into DNA.

Selective Media

Growth media that inhibits certain microbes while allowing others to grow.

Differential Media

Growth medium that differentiates between microbes based on biochemical reactions.

Acid-fast Staining

Staining method used for Mycobacterium species due to their waxy mycolic acid.

Obligate Aerobes

Organisms that require oxygen to grow.

Obligate Anaerobes

Organisms that cannot tolerate oxygen.

Facultative Anaerobes

Organisms that can grow in the presence or absence of oxygen.

Bacteriostatic Agents

Agents that inhibit bacterial growth.

Bactericidal Agents

Agents that kill bacteria.

Pasteurization

A process that reduces microbial load in liquids using mild heat.

Electron Transport Chain

A series of protein complexes that generate ATP through oxidative phosphorylation.

Phenol Red Broth Test

A test used to detect bacterial fermentation of carbohydrates.

Nitrate Reduction

The process of some bacteria reducing nitrate to nitrogen gas in anaerobic respiration.

Reservoir

The primary habitat of a pathogen.

Vector

An organism that transmits a pathogen.

Koch’s Postulates

Criteria used to establish a microbe as the cause of a disease.

Nosocomial Infection

Infections acquired in a hospital setting.

Virulence Factors

Traits that enhance a microbe’s ability to cause disease.

Endotoxins

Toxins found in Gram-negative bacteria released upon cell death.

Exotoxins

Secreted proteins by bacteria that cause damage.

Autoclave

A device that uses high-pressure steam to sterilize equipment.

Natural Killer (NK) Cells

Cells that kill virus-infected and cancerous cells by inducing apoptosis.

Signs of Inflammation

Redness, heat, swelling, pain.

Complement Proteins

Proteins that enhance phagocytosis, lyse bacteria, and promote inflammation.

Herd Immunity

When a large portion of a population is vaccinated, reducing the spread of disease.

Monoclonal Antibodies

Antibodies that specifically bind to pathogens or antigens for diagnostics.

Active Immunity

Immunity developed from infection or vaccination.

Passive Immunity

Immunity transferred from another source.

β-lactam Antibiotics

Antibiotics that inhibit bacterial cell wall synthesis.

Fluoroquinolones

Antibiotics that inhibit DNA gyrase to kill bacteria.

Broad-spectrum Antibiotics

Antibiotics that target a wide range of bacteria.

Narrow-spectrum Antibiotics

Antibiotics that target specific types of bacteria.

Antibiotic Resistance

The development of bacteria to survive exposure to antibiotics.