Exam 1 Terms Flashcards
Define cocci
Bacterial morphology describing a spherical shape
Define bacilli
Bacterial morphology describing rod shaped bacteria, can be pleomorphic
Define spirochete
Bacterial morphology describing helical (squiggly) shape
Define pleomorphism
The ability of some microorganisms to alter their shape in response to environmental conditions
Define flagella
Exterior protein filaments involved in movement
Pili or fimbriae
Protein fibers, smaller than flagella, which allow for attachment to a host. “Hair like structures”
What are the important components of endospores?
They are: Highly durable (think genetic bunker) SURVIVAL
Dehydrated cells with thick cell walls that are resistant to heat and drying
Remain dormant for long time
Only in some gram positive bacteria
Returns to vegetative (growing) state when environmental conditions improve
Capsules
Made of polysaccharides and covers the cell wall to shield the bacteria from phagocytic responses
Think invisibility cloak
Phagocytosis
The ingestion of bacteria or other material by phagocytes and amoeboid protozoans
Microbiome
A community of microorganisms living in a particular environment
Biofilm
An assemblage of microbial cells adhering to a surface (living or no living)and enclosed in a polysaccharide matrix; they help make bacteria resistant to antimicrobial agents and physical disruption
Compare similarities in prokaryotes and eukaryotes
Both have DNA and ribosomes and organelles
Can be asexual
Can have flagellum
Contrast differences in prokaryotes and eukaryotes
Eukaryotes have membrane bound nucleus containing genetic info, prokaryotes do not.
Eukaryotes have multiple strands of diploid genome, prokaryotes have a single circular haploid genome and can contain plasmids
Eukaryotes don’t have a cell wall except for fungi, all prokaryotes do.
Eukaryotes produce sexual and asexual, prokaryotes on sexual by binary fission
How do you classify bacteria?
Using the genus and species. Genus is always capitalized, species is never. Both can be italicized or underlined, but never both.
Compare strains and isolates
A strain is a genetically identical or clonal representatives of a species. An isolate is a representative bacterial colony taken from a specific source, like a Petri dish.
Different isolates can be the same strain, but different strains can not be the same isolate.
Koch’s postulates
- Microorganism must be present in every case of the infectious disease
- Microorganisms can be isolated in pure culture
- Inoculation of pure culture into animals produces similar disease
- The same species of microorganisms must be recovered from the diseased animal.
Are they necessarily true with modern information? No, none are.
Host
The patient
Parasite
Anything that invades and causes infectious disease
Pathogen
A microorganism capable of causing an infectious disease
Primary pathogen
Microorganism that regularly causes infection and disease in non immune host. (You can get it with a healthy immune system)
Opportunistic pathogen
Microorganism that rarely causes disease in healthy humans, rather it gets you when your defense systems have already been compromised
Commensalism
Colonization. A relationship where one benefits and the other neither benefits no retains damages
Symbiosis
A mutually beneficial relationship
Parasitism
A relationship where one benefits and the other is harmed
Infection
Invasion and multiplication of microorganisms in or on a host
Virulence
The degree of pathogenicity and extent to which microorganisms can cause damage to the infected host
Carrier
An infected host that carries a latent form of a microorganism due to genetics.
Typhoid Mary
Examples of host defenses
Microbiome An atomic barriers Cilia in respiratory tract Mucous layer Stomach acid Peristalsis in GI tract Chemical inhibitors antibodies Neutrophils
Behaviors leading to disease
Behaviors Occupation Age, gender, genetics Prior viral infections foreign body Diabetes Burns Immunosuppressive drugs
Microbial factors leading to disease
Evade immune response (capsules) Antibiotic cleaving Attachment ability Exotoxins Endotoxins Enzyme excretion
Disease transmission
Endogenous sources
Exogenous sources
Within body
Breaks in natural barrier after trauma, change in host defense mechanisms
Outside of body
Inhalation, ingestion, direct contact, animal contact, fomites (inanimate objects it can live on)
Sanitation
Reduces number of microorganisms on inanimate objects as judged by public health standards
Antiseptics
Chemicals applied to SKIN to kill pathogens and reduce normal flora organisms
Disinfectant
Chemicals applied to inanimate objects to destroy pathogenic microorganisms
Sterility
An absolute state that is free from all VIABLE forms of microorganisms
Cide/cidal
To kill
Stasis/static
To prevent multiplication
Sepsis
Toxic condition from microbial presence or toxins in the body
Asepsis
A goal of reaching a condition free from viable organisms
Nosocomial infection
Infection acquired in hospital or other health care provider
What is the purpose of soap?
To remove oils and dead skin cells that may harbor microorganisms. Does not kill microbes, it gets rid of their environment
