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**