Microbiology Flashcards
Three domains
- bacteria
- archaea
- eukarya
major groups of human pathogens
- protozoa
- fungi
- bacteria
- viruses
features of eukaryotes
linear chromosomes with histones, introns and axons, 80S ribosomes, no cell wall and cell cycle
features of prokaryotes
single-celled, introns rare, single circular chromosome, 70S ribosomes, cell wall
define nucleoid
contains DNA and proteins, no membrane, chromosomes are single and circular
how does energy generation occur across the cytoplasmic membrane?
electrons are released from compounds in the cytoplasm and passed through a series of electron acceptors. Protons are passed out creating a gradient.
what allows bacteria to stick together?
fimbriae and pili
what is needed for prokaryotic growth?
food, temp, pH, osmotic protection and oxygen
gram classification of bacteria
stain bacteria purple
plankton growth
- initial attachment
- irreversible attachment to each other
- maturation one- growth
- maturation two
- dispersion- spreads
how can microorganisms be classified?
- appearance/ structural features
- gram staining
- growth requirements
- type of media
- biochemical tests
- molecular tests
describe different shapes of bacteria
cocci, bacilli and spiral-shaped
obligate aerobes
require oxygen
obligate anaerobes
killed by oxygen
facultative anaerobes
tolerate oxygen
capnophillic
prefer high CO2 levels
selective media
presence of specific substances for growth, inhibits others
differential media
used to differentiate organisms that are closely related
heamolysis
disruption of red blood cells
biochemical test
coagulate and catalase test
define microbiome
combined genetic material of microorganisms in a particular environment
define endogenous
microorganisms
define exogenous
not of the normal flora
define pathogenesis
parasite life cycle
define virulence
capacity of a microbe to cause damage to the host
define commensal
organism that is part of the normal flora (endogenous)