2: Systemic Bacteriology I

Question 1

Generally, microbes are classified based on their ___.

Answer 1

appearance

Question 2

Cell walls can be classified as either __ __ or __ __.

Answer 2

Gram positive or Gram negative

Question 3

Apart from Gram staining, what is another staining method used to identify microbes?

Answer 3

Ziehl Neelson stain

Question 4

Name three common shapes of bacteria.

Answer 4

Cocci (spheres)

Bacilli (rods)

Spiral-shaped

Question 5

What are sphere-shaped bacteria called?

Answer 5

Cocci

Question 6

What are rod-shaped bacteria called?

Answer 6

Bacilli

Question 7

Apart from spheres and rods, what other shape can bacteria be?

Answer 7

Spiral-shaped

Question 8

What is a single sphere-shaped bacteria called?

Answer 8

A coccus

Question 9

What is a bacteria consisting of two cocci in one plane?

Answer 9

Diplococcus

Question 10

What is a chain of cocci called?

Answer 10

Streptococcus

Question 11

What is a clump of cocci called?

Answer 11

Staphylococci

Question 12

What is a rod-shaped bacteria called?

Answer 12

Bacilli

Question 13

What are slightly curved bacteria called?

(For extra points, what Gram classification are they?)

Answer 13

Vibrio

Gram negative

Question 14

What are spiral-shaped bacteria called?

Answer 14

Spirillum

Question 15

What is a spore?

Answer 15

An inert structure which is resistant to physical and chemical challenge

Question 16

Give an example of a bacterial species which produces spores.

Answer 16

C. difficile

Question 17

What is a Gram stain?

Answer 17

A purple/violet dye which is RETAINED by Gram positive bacteria

Question 18

Which type of bacteria retains Gram stain?

Answer 18

Gram positive bacteria

Question 19

Which type of bacteria doesn’t retain Gram stain?

Answer 19

Gram negative bacteria

Question 20

What colour do Gram positive bacteria turn after staining?

Answer 20

Dark purple

Question 21

What colour do Gram negative bacteria turn after staining?

Answer 21

Pink (lighter than purple)

Question 22

E. coli is Gram…

Answer 22

E. coli is Gram negative

Question 23

Staph. aureus is Gram…

Answer 23

Staph. aureus is Gram positive

Question 24

What is a notable organism which doesn’t stain well with Gram stain?

Answer 24

Mycobacterium tuberculosis

Question 25

Mycobacterium tuberculosis stains (well / poorly) with Gram stain.

Answer 25

poorly

Question 26

Killed by oxygen

Tolerate oxygen

Grow in oxygen

Require oxygen

Match these definitions to aerobes, obligate aerobes, obligate anaerobes and facultatitive anaerobes.

Answer 26

Aerobes - grow in oxygen

Obligate aerobes - require oxygen

Obligate anaerobes - killed by oxygen

Facultative anaerobes - tolerate oxygen

Question 27

Microbes can also be classified by their ability/inability to use which gas?

Answer 27

Oxygen

Question 28

What is selective media?

Answer 28

Media which permits the growth of one organism over others

Question 29

What is differential media?

Answer 29

Media which facilitates the differentiation of organisms for identification

Question 30

What are the three types of haemolysis?

Answer 30

Alpha

Beta

Gamma

Question 31

What is characteristic of Alpha haemolysis?

Answer 31

Greening of the colonies

Question 32

What are two organisms which show alpha haemolysis (greening)?

Answer 32

Strep. pneumoniae

Strep. Viridans group

Question 33

What is characteristic of Beta haemolysis?

Answer 33

Gold colouring

Question 34

What is Gamma haemolysis?

Answer 34

No haemolysis at all

Question 35

What special test can be used to identify microbes?

Answer 35

MALDI-TOF

Question 36

In terms of taxonomy, which two bits of information must be included when referring to a microbe?

Answer 36

Genus (e.g Bacillus)

Species (e.g subtilis)

Question 37

What are some examples of microbiology tests which could be carried out in a clinical environment to identify microbes responsible for disease?

Answer 37

Blood culture

Urine culture

Faeces culture

Pus samples