formative quiz flashcards
what type of bacterium is Escherichia coli?
Gram-negative bacillus
topical anti fungal preparations are used to treat what?
fungal skin infections
how does genetic variation in bacteria occur?
through spontaneous mutation in the chromosome and transfer of plasmids between bacteria
are all penicillins inactivated by beta-lactamase?
no, some penicillins are resistant to beta-lactamase like flucloxacillin
is an organism sensitive to an antibiotic is always killed by it?
no, antibiotics can be bacteriocidal and kill bacteria or bacteriostatic and prevent its replication
do bacterial exotoxins only act at the site of infection?
no, bacterial exotoxins are secreted by the organism or released during cell lysis and can enter the bloodstream and cause systemic effects
can viruses only be cultured inside other cells?
yes, viruses require a host cells nucleic acids and organelles in order to replicate
is bacterial DNA only found in the chromosome?
no, as well as chromosomal DNA bacteria contain small loops of DNA called plasmids.
are carbapanems members of the beta-lactam class of antibiotics?
yes, penicillin, cephalosporins and carbapanems are all beta lactic antibiotics. they all possess the typical chemical structure the beta lactic ring
is all antibiotic resistance caused by genes carried on plasmids?
no, spontaneous mutations on bacterial chromosomal DNA can arise which result in antibiotic resistance
are antiviral drugs virucidal?
no, antiviral drugs are all virustatic they inhibit growth and or replication of viruses
is antiseptic safe to use on the skin?
yes, clinical practice examples are iodine chlorhexididne and isopropyl alcohol
are capsulate organisms (eg. pneumococcus ) resistant to phagocytosis
yes, the capsule enables the organism to evade phagocytosis
how is malaria diagnosed?
visualisation of parasites in a peripheral blood film, usually done using thick or thin smears, thick smears detect presence of parasite thin smears allow identification of species
what type of bacteria is streptococcus pyogenes?
gram positive coccus
does chlorination of drinking water prevent intestinal parasites?
no an example of a parasite not killed by chlorination is cryptosporidium
should live vaccines be given to pregnant or immunocompromised patients?
no, live vaccines carry theoretical risk of infection to the foetus or immunocompromsed patient
is aciclovir used to treat all herpes infections?
no, aciclovir is used to treat herpes simplex and varicella zoster infections, many other herpes viruses require other antiviral agents
what is co-trimoxazole a combination of?
trimethoprim and sulphamethoxazole
does programmed cell death involve phagocytosis?
yes, this is a clean form of cell death known as apoptosis
does vasoconstriction promote bleeding during injury?
no, vasoconstriction limits blood flow and prevents bleeding.
what is the most common immunotherapy side effect?
colitis in 30% of dual immunotherapy patients
what type of cells do the majority of cancers come from?
epithelial cells (around 85%)
what is haemostasis?
cessation of bleeding after an injury
