Bacteria

Question 1

difference btw gram (+) and gram (-)

Answer 1

positive has thicker layer of PG, negative has thiner layer btw two cell membranes.
positive will bind to blue
negative will bind to red.

Question 2

staphylococcus

Answer 2

gram (+): commensal skin -> armpit, groin nostrils
s. aureus- skin and soft tissue infections
MRSA - penicillin resistant
all coagulase positive

coagulase negative staphylococci
not pathogenic, iatrogenic infections ie. IV lines

Question 3

streptococcus

Answer 3

gram (+) commensal in oropharynx GAS
s. pyogenes = strep throat & necrotizing fascitis.
S .pneumoniae - otitis media, pneumonia, meningitis (vaccination against)

commensal residents of the GI tract
s. agalactiae - GBS passes mom to baby. tested. UTI to neontal meningitis

Question 4

corynebacteria

Answer 4

gram (+): usually commensal.

c.diptheria = ulcerative disease in throat = vaccine now.

Question 5

listeria

Answer 5

gram (+): in GI of animals. bad when introduced to humans. severe GI symptoms.
lives cell-to-cell, hides from immunity. crosses cell walls
l. monocytogenes
meningitis and spontaneous abortion

Question 6

gram (-) 3 types

Answer 6

diplococci
respiratory
enteric

Question 7

neisseria

Answer 7

diplococci (-)
meningiditis = commensal resident of the oropharynx until it is activated. = meningitis. vaccinate against
gonorrhea = not commensal (not normal in screening). STI

Question 8

haemophilus

Answer 8

respiratory (-):
H. influenzae = respiratory tract infection.
serotype type b - more pathogenic than other strains
epiglottis and infantile death
rare in canada -vaccine success.

Question 9

E.coli

Answer 9

enteric food poisioning. diarrhea in immuno-competent

Question 10

Can’t gram stain 3 types of bacteria

Answer 10

spirochetes = too small - need EM
mycobacteria = special stain
mycoplasma = no cell wall