Video: Microbes and Bacteria - Vocabulary Flashcards

100 vocabulary flashcards covering bacteria and microbiology concepts typical of microbiology lectures.

Bacteria

Single-celled prokaryotic microorganisms; range from harmless to pathogenic and many are beneficial.

Prokaryote

An organism lacking a nucleus; includes bacteria and archaea.

Eukaryote

Organism with a nucleus and membrane-bound organelles.

Archaea

A domain of single-celled prokaryotes distinct from bacteria, often found in extreme environments.

Gram-positive

Bacteria with a thick peptidoglycan layer that retain crystal violet stain (purple under Gram stain).

Gram-negative

Bacteria with a thin peptidoglycan layer and outer membrane; counterstain pink/red.

Cocci

Spherical-shaped bacteria.

Bacilli

Rod-shaped bacteria.

Spirilla

Spiral-shaped bacteria with rigid bodies.

Spirochetes

Long, flexible spiral bacteria.

Escherichia coli

Common gut bacterium; model organism; some strains are pathogenic.

Staphylococcus aureus

Gram-positive cocci in clusters; can cause skin infections and MRSA.

Staphylococcus epidermidis

Skin commensal; often an opportunistic pathogen in hospitals.

Streptococcus pneumoniae

Gram-positive diplococcus; causes pneumonia and meningitis.

Streptococcus pyogenes

Group A strep; causes strep throat and other infections.

Bacillus subtilis

Gram-positive rod; soil bacterium; model organism; forms endospores.

Bacillus cereus

Bacterium that can cause food poisoning.

Salmonella enterica

Gram-negative rod; causes gastroenteritis and typhoid fever.

Shigella dysenteriae

Causes shigellosis; highly infectious Gram-negative rod.

Campylobacter jejuni

Curved Gram-negative rod; leading cause of bacterial gastroenteritis.

Vibrio cholerae

Curved Gram-negative rod; causes cholera through a toxin.

Helicobacter pylori

Curved Gram-negative rod; colonizes the stomach; linked to ulcers.

Listeria monocytogenes

Gram-positive rod; foodborne pathogen; can cause listeriosis.

Clostridioides difficile

Anaerobic, spore-forming bacterium; causes antibiotic-associated diarrhea.

Clostridium botulinum

Produces botulinum toxin; causes botulism; anaerobic spore-former.

Clostridium tetani

Causes tetanus; anaerobic spore-former.

Pseudomonas aeruginosa

Gram-negative rod; opportunistic pathogen; highly resistant and versatile.

Klebsiella pneumoniae

Gram-negative rod; pneumonia and other infections; often antibiotic resistant.

Enterococcus faecalis

Gram-positive cocci; normal gut flora; can cause nosocomial infections.

Neisseria meningitidis

Gram-negative diplococcus; causes meningitis and sepsis.

Neisseria gonorrhoeae

Gram-negative diplococcus; causative agent of gonorrhea.

Mycobacterium tuberculosis

Acid-fast rod; etiological agent of tuberculosis.

Mycobacterium leprae

Cause of leprosy; grows slowly in host tissues.

Chlamydia trachomatis

Obligate intracellular pathogen; causes chlamydia and trachoma.

Rickettsia rickettsii

Obligate intracellular bacterium; causes Rocky Mountain spotted fever.

Borrelia burgdorferi

Spirochete; causes Lyme disease.

Treponema pallidum

Spirochete; causes syphilis.

Streptomyces coelicolor

Soil actinobacterium; known for antibiotic production; model organism for Streptomycetes.

Lactobacillus acidophilus

Lactic acid bacterium; probiotic; common in yogurt.

Bifidobacterium bifidum

Probiotic gut bacterium; part of healthy microbiota.

Saccharomyces cerevisiae

Baker's yeast; model eukaryotic organism; used in baking and fermentation.

Saccharomyces boulardii

Probiotic yeast marketed for gut health.

Staphylococcus aureus MRSA

Methicillin-resistant Staphylococcus aureus; antibiotic-resistant pathogen.

Escherichia coli K-12

Non-pathogenic lab strain used for teaching and research.

Bacillus anthracis

Causes anthrax; spore-forming Gram-positive rod; highly dangerous.

Streptococcus mutans

Oral bacterium linked to dental caries.

Streptococcus thermophilus

Used in dairy fermentation; contributes to yogurt cultures.

Actinobacteria

Phylum of high G+C Gram-positive bacteria including many soil microbes and pathogens.

Firmicutes

Phylum of Gram-positive bacteria; includes Bacillus, Clostridium, Streptococcus.

Proteobacteria

Major phylum of Gram-negative bacteria; includes many pathogens.

Cyanobacteria

Photosynthetic bacteria that release oxygen; important in early Earth and modern ecosystems.

Gram stain

Differential staining method to classify bacteria as Gram-positive or Gram-negative.

Peptidoglycan

Polymer forming bacterial cell walls; thick in Gram-positive bacteria.

Capsule

Gelatinous outer layer aiding immune evasion and adherence.

Flagellum

Whip-like structure enabling bacterial motility.

Pili

Hair-like appendages for attachment and DNA transfer.

Biofilm

Structured community of microbes attached to a surface; often resistant to treatment.

Oxidase test

Chemical test to detect certain cytochrome oxidases in bacteria.

Catalase test

Test for the enzyme catalase; bubbles form with hydrogen peroxide if positive.

Antisepsis

Reduction of pathogens on living tissue to prevent infection.

Antibiotic resistance

Bacteria's ability to survive exposure to antibiotics.

Quorum sensing

Cell-density–dependent communication that regulates gene expression.

Probiotic

Live microorganisms that confer a health benefit when consumed.

Bacteriophage

Virus that infects and replicates within bacteria.

Antibiotic

Substance that kills or inhibits growth of bacteria.

Sterilization

Process that destroys all forms of life, including spores.

Disinfection

Reduces viable microorganisms on inanimate objects; may not kill spores.

Pathogen

Microorganism capable of causing disease.

Opportunistic pathogen

Causes disease mainly in hosts with weakened defenses.

Anaerobe

Organism that does not require oxygen for growth; may be harmed by oxygen.

Aerobe

Organism that requires oxygen for growth.

Facultative anaerobe

Can grow with or without oxygen, adapting to different environments.

Endospore

Dormant, highly resistant structure formed by some bacteria to survive harsh conditions.

Sporulation

Process of endospore formation in certain bacteria.

Model organism

A species used widely in research to understand biology, e.g., E. coli, S. cerevisiae.

Culture medium

Substance providing nutrients for microbial growth; can be solid or liquid.

Growth medium

Medium used to cultivate microorganisms; often contains nutrients and minerals.

Gram staining procedure

Four-step process: stain with crystal violet, apply iodine, decolorize, counterstain.

Culture

Growth of microorganisms in a controlled environment.

Microbiome

Community of microorganisms living in a specific environment, such as the gut.

Fermentation

Metabolic process producing energy without oxygen; used in food production.

Pathogenicity

Ability of a organism to cause disease.

Virulence factor

Molecule that enables a pathogen to cause disease.

Biohazard

Biological substance presenting a risk to health.

Petri dish

Flat dish used to culture microorganisms on solid media.

Colony

Visible group of identical microbes arising from a single cell.

Aseptic technique

Procedures to prevent contamination of sterile materials.

Sterile

Free from all living microorganisms.

Contamination

Unwanted introduction of microbes into an environment or sample.

Agar

Gelatinous substance used to solidify growth media in plates.

Nutrient broth

Liquid medium providing nutrients for microbial growth.

Koch's postulates

Historical criteria linking a microbe to a disease.

Pasteurization

Mild heating to reduce pathogens and extend shelf life.

Autoclave

Device that sterilizes using pressurized steam.

Incubation

Maintaining suitable conditions for microbial growth.

Colony-forming unit

Unit estimating viable bacteria by counting colonies.

Nutrient agar

Solid growth medium made with agar and nutrients.

Obligate intracellular parasite

Organism that can only replicate inside host cells.

Gram-variable

Bacteria displaying inconsistent Gram staining results.

Mesophile

Organism that grows best at moderate temperatures (roughly 20–45°C).