Pathogenisis Of Bacteria Flashcards
(26 cards)
What is the largest organ of the body?
Skin
Skin serves as an effective barrier against most microorganisms when unbroken.
What are common openings in the skin through which microbes can enter?
- Hair follicles
- Sweat glands
Name a common disease contracted via the respiratory tract.
- Common cold
- Flu
- Tuberculosis
- Whooping cough
- Pneumonia
- Measles
- Strep Throat
- Diphtheria
Define pathogen.
A microorganism capable of causing disease.
What does infection mean in a medical context?
Multiplication of an infectious agent within the body.
What is the process called where bacteria, parasites, fungi, and viruses enter host cells?
Invasion
How do fecal-oral diseases spread?
By contaminated hands, fingers, food, or water.
What is an opportunistic pathogen?
Microbes that can cause disease only in immunocompromised people.
Define virulence.
A measure of a microbe’s ability to cause disease.
What does ID50 represent?
The number of organisms required to cause disease in 50% of the population.
True or False: A low ID50 indicates a highly virulent organism.
True
What are the two main mechanisms by which bacteria cause symptoms of disease?
- Production of toxins (exotoxins and endotoxins)
- Induction of inflammation
List some common diseases contracted via the gastrointestinal tract.
- Salmonellosis
- Shigellosis
- Cholera
- Ulcers
- Botulism
What are the determinants of bacterial pathogenesis?
- Transmission
- Adherence to Cell Surfaces
- Invasion, Inflammation, & Intracellular Survival
- Toxin Production
- Immunopathogenesis
How can transmission occur?
- Human to human (direct contact)
- Indirectly via a vector (e.g., ticks or mosquitoes)
- Nonhuman to human processes
What is zoonosis?
Human diseases for which animals are the reservoir.
What is the third portal of entry for microorganisms?
Parenteral
How do microorganisms enter the body through the parenteral route?
- Punctures
- Injections
- Bites
- Scratches
- Surgery
What are bacterial virulence factors?
- Adherence Factors
- Antiphagocytic Factors (Capsule)
- Enzymes
- Toxins
What is the main mechanism by which bacteria adhere to human cells?
Pili
What is the role of the glycocalyx in bacterial adherence?
It is a polysaccharide ‘slime layer’.
What are the two types of toxins produced by bacteria?
- Exotoxins
- Endotoxins
What does the conjunctiva cover?
The eyeball and lines the eyelid.
What are chronic carriers in the context of infectious diseases?
Individuals who remain asymptomatic after recovery but still harbor the organism.
