Generic Micoorganism Principles Flashcards
how do we classify microorganisms
size and shape presence of nucleus nature of genetic material number of chromosomes nature of cells wall if present type of cell membrane sterols
cell type of viruses, bacteria, fungi, and parasites
viruses - acellular
bacteria - prokaryotic
fungi - eukaryotic
parasites - eukaryotic
nucleus presence of viruses, bacteria, fungi, and parasites
viruses - none
bacteria - none
fungi - yes
parasites - yes
DNA/RNA/both in viruses, bacteria, fungi, and parasites
viruses - DNA or RNA
bacteria - Both
fungi - Both
parasites - Both
chromosomes in viruses, bacteria, fungi, and parasites
viruses - nucleocaspid
bacteria - 1 chromosome
fungi - more than 1
parasites - more than 1
ribosomes in viruses, bacteria, fungi, and parasites
viruses - none
bacteria - 70S ribosomes
fungi - 80S ribosomes
parasites - 80S ribosomes
cell wall composition in viruses, bacteria, fungi, and parasites
viruses - none
bacteria - peptidoglycans
fungi - chitin
parasites - none
membrane sterols in viruses, bacteria, fungi, and parasites
viruses - no membrane, so no sterols
bacteria - membrane, but no sterols
fungi - membrane with ergosterols
parasites - membrane with sterols
what is defined as the ability of a pathogen to establish an infection
infectivity
what is defined as the ability to cause disease
pathogenicity
what bacteria use pili (hair like adherens) to adhere to surfaces of host cells
E coli
what bacteria have fimbriae which are similar to pili that adheres to the surfaces of host cells
Group A streptococci
adherence enhances the ___ of the microorganism by preventing it from being carried away by mucus or fluids in the body
infectivity
more adherence = more infective
what is the ability to penetrate a hosts defenses
invasion
some microorganisms have what that help facilitate the invasion process
give examples
enzymes
ex. collagenase and hyaluronidase
what is it called when a microorganism is capable to change the shape of their surface antigen to escape detection by the humans antibodies
antigenic switching
what species is capable of antigenic switching
trypanosoma
how does trypanosoma facilitate antigenic switching
trypanosoma enters the body and stimulates the production of antibodies
within a matter of hours, some of the trypanosoma switch the variable surface glycoprotein covering themselves to a new antigenic VSG to slip the bodies defense mechanisms
what is it called
ability to cause serious illness
virulence
give an example of something that make a microorganism more virulent
example
poisons or toxins produced which are extremely harmful to the patient
ex. toxin produced by clostridium botulinum
what is a hospital acquired infection called
nosocomial
what is a disease caused by health professionals called
iatrogenic
iatrogenic disease caused by health professionals is usually due to what
washing hands
what is a common hospital acquired infection that causes diarrhea and could be fatal
clostridium difficile