8/20- Exam 1 Flashcards
What are cell organelles?
Structures within cells responsible for various functions, including metabolism.
What distinguishes Gram-negative from Gram-positive bacteria?
Gram stain; Gram-positive have a thicker peptidoglycan layer, Gram-negative have LPS and two membranes.
What is a prokaryotic organism?
An organism without a membrane-bound nucleus; includes bacteria and archaea.
What is a eukaryotic organism?
An organism with a membrane-bound nucleus; includes all other living organisms.
What is a haploid organism?
An organism with a single set of chromosomes.
What is a diploid organism?
An organism with two sets of chromosomes, one from each parent.
What is lipopolysaccharide (LPS)?
A component of Gram-negative bacteria’s outer membrane that activates host inflammatory responses.
What is peptidoglycan?
A polymer found in bacterial cell walls, thicker in Gram-positive bacteria.
What does saccharolytic mean?
Bacteria that metabolize sugars to derive energy.
What does asaccharolytic mean?
Bacteria that use amino acids to derive energy.
What is a biofilm?
A community of microorganisms attached to a surface with a matrix.
What is the proteome?
The total set of proteins in a tissue or body fluid.
What are caries?
Tooth decay caused by bacteria in the enamel and dentin.
What is plaque?
A soft biofilm that builds up on teeth from bacteria attaching to the tooth surface.
What is calculus?
Hardened plaque on teeth due to mineral deposition, also known as tartar.
What is a pellicle?
A thin proteinaceous layer on enamel from glycoproteins in saliva.
What are glucans?
Polysaccharides made from glucose by S. mutans, contributing to biofilm formation.
What are fructans?
Polysaccharides made from fructose by S. mutans, also contributing to biofilm formation.
What are the major divisions of life?
Eukaryotes and prokaryotes (bacteria and archaea).
How do eukaryotic and prokaryotic cells differ?
Eukaryotic cells have a membrane-bound nucleus and more organelles; prokaryotic cells do not.
What is unique about viruses?
They are neither prokaryotes nor eukaryotes.
What is the structure of a bacterial cell?
Includes fimbriae, flagella, LPS, and a capsule.
What is the role of the cell membrane in bacteria?
It separates the cell’s interior from the environment and controls molecule movement.
How does bacterial size compare between prokaryotes and eukaryotes?
Prokaryotes: 1-10 microns, Eukaryotes: 10-100 microns.
What contributes to plaque, and calculus,
Plaque is biofilm; if not removed, it mineralizes into calculus
What is the difference between saccharolytic and asaccharolytic bacteria?
Saccharolytic bacteria break down sugars; asaccharolytic bacteria break down amino acids.
How do saccharolytic bacteria contribute to caries?
They lower pH, leading to tooth demineralization and caries.
What is gingival crevicular fluid?
A fluid in the gingival sulcus that cleans the sulcus, supports adhesion, and has antimicrobial properties.
What is the role of saliva in oral health?
It lubricates, protects, buffers, and has antibacterial properties.
What is the role of gingival crevicular fluid in periodontal disease?
It provides nutrients for subgingival bacteria, contributing to periodontal pathogens.
How does calculus promote periodontal disease?
It creates an environment for asaccharolytic bacteria, leading to hydrogen sulfide and bad breath.
How does the dental pellicle form?
It forms within seconds after cleaning by binding of proteins in saliva to enamel.
How do biofilms contribute to oral disease?
Biofilms produce acids that contribute to caries and lead to periodontal disease.
What is the significance of modern molecular biology in dentistry?
It enables personalized dentistry based on individual genetics and oral biomes.
