Topic 1 - 1 Flashcards
What are the 3 classes of microbes?
Prokaryotes
Small eukaryotes
Viruses
What is microbiota?
Microoranisms that live in or on a normal human body, without causing disease.
What is another name for microbiota?
Normal flora
What is mutualism?
A symbiotic (living together) relationship that benefits both species (in body, benefit humans and microbiota)
What is commensalism?
A symbiotic (living together) relationship that benefits only one species, but not at expense of the other species (in body, microbiota benefit without harming human)
Four outcomes of microoranisms encounters?
1) Pass through body harmlessly
2) Colonize the body and become part of the microbiata
3) Establish an infection in the body
4) Establish an infection in the body AND cause disease
Define Infection
Refers to the invasion or colonization of the body by pathogenic (disease-causing) microorganisms. Does NOT always result in damage to the body.
Define disease
Injury to the body that impairs function
What influences the relationship between the human body and a microorganism?
1) pathogenicity (ability to cause disease)
2) the resistance or susceptibility of the host (ex. defence mechanisms of the host, such as innate and adaptive immune responses)
Bacterial structure? (i.e. structures of a prokaryote)
Has cytoplasm, nucleoid, cytoplasmic membrane (phosphoypid bilayer), ribosome
Lacks membrane-bound organelles
Some have pili, flagella, capsule, cell wall
Size difference between eukaryotes and prokaryotes?
~10-100 times larger (10-100 um vs. 0.1 um)
Shapes of bacterial cells? (hint- 4 types)
Coccus (spherical)
rod-shapped (bacilus)
Spiral rods
vibroid (curved rods)
Bacterial Cell wall - what is it made of?
Peptidoglycan (PG), which is a covalently bonded glycan backbone w/ peptides
Cell envelope
Cell wall + cytoplasmic membrane
Flagella
Gives bacteria swimming motility (ability to move independently)