2.1 Bacteria subgroups

Question 1

describe the cell wall of gram positive bacteria

Answer 1

one thick cell wall

Question 2

describe the cell wall of gram negative bacteria

Answer 2

double layered cell wall, a layer of outer membrane to protect the inner thin cell wall

Question 3

which bacteria stains purple first time

Answer 3

gram positive

Question 4

what are round bacteria called

Answer 4

cocci

Question 5

what are thin rod-like bacteria called

Answer 5

bacilli

Question 6

describe atypical bacteria

Answer 6

they have no cell wall, so live inside other cells

Question 7

describe the coagulase test

Answer 7

used to differentiate between 2 gram positive cocci bacteria: Staphylococcus aureus (positive) from Coagulase Negative Staphylococcus. Coagulase is an enzyme produced by S. aureus that converts (soluble) fibrinogen in plasma to (insoluble) fibrin, so if the bacteria can clot the plasma, it’s S.Aureus

Question 8

describe the haemolysis test

Answer 8

can differentiate between streptococci. Beta-haemolytic bacteria completely digest blood, alpha= partial and gamma/non= not at all

Question 9

example of gram positive cocci

Answer 9

staphylococci or streptococci

Question 10

example of gram positive bacilli

Answer 10

listeria or clostridium

Question 11

example of gram negative cocci

Answer 11

N.Meningitidis/meningococci or N.Gonorrhoea/gonococci

Question 12

example of gram negative bacilli

Answer 12

Pseudomonas, haemophilus and enterobacteraciae

Question 13

what are enterobacteraciae

Answer 13

type of gram negative bacilli bacteria, for example E.coli