(8)

Question 1

What type of molecule is found in the cell wall of acid-fast bacteria?

Answer 1

Mycolic acids

Question 2

What is the primary stain of the Ziehl-Neelsen acid-fast procedure? Decolorizer? Counterstain?

Answer 2

Primary stain- carbolfuchsin (lipid-soluble & penetrates the waxy cell wall)
Decolorizer- acid alcohol
Counterstain- brilliant green

Question 3

What color do acid-fast cells appear after the acid-fast procedure? Non-acid-fast?

Answer 3

Acid-fast cells are reddish-purple

Nonacid-fast cells are the color of the contrasting counterstain

Question 4

What genus of bacteria can be detected using the acid-fast procedure?

Answer 4

Mycobacterium

Question 5

What disease can be diagnosed using the acid-fast procedure?

Answer 5

Leprosy and tuberculosis

Question 6

Insoluble, mucoid, extracellular material surrounding some bacteria; composed of mucoid polysaccharides or polypeptides that repel most stains

Answer 6

capsule

Question 7

Is the capsule staining procedure a negative stain, positive stain, or both?

Answer 7

Negative stain

Question 8

What is the medical importance of a capsule?

Answer 8

A capsule stain is a differential stain used to detect cells capable of producing an extracellular capsule. Capsule production increases virulence in some microbes (such as the anthrax bacillus Bacillus anthracis and pneumococcus Streptococcus pneumoniae) by making them less vulnerable to phagocytosis.

Question 9

What stains are used in a capsule stain?

Answer 9

Maneval’s stain & congo red stain

Question 10

What color is the capsule after staining?

Answer 10

The capsule is unstained and appears as a white halo between the cells and the colored background

Question 11

Dormant, highly resistant form of bacterium; produced only by species of Bacillus, Clostridium and a few others; dormant form of the bacterium that allows it to survive poor environmental conditions

Answer 11

endospore

Question 12

spores are resistant to heat and chemicals because of a tough outer covering made of this protein. It also resists staining.

Answer 12

keratin

Question 13

An actively metabolizing & growing cell.

Answer 13

vegetative cell

Question 14

a cell that forms spores

Answer 14

spore mother cells

Question 15

middle of the cell

Answer 15

central

Question 16

at the end of the cell

Answer 16

terminal

Question 17

between the end and middle of the cell

Answer 17

subterminal

Question 18

round & shaped like a sphere

Answer 18

spherical

Question 19

oval

Answer 19

ellipitical

Question 20

A heterotroph that digests dead organic matter; a decomposer

Answer 20

saprophytes

Question 21

produces spores

Answer 21

sporulate

Question 22

start growing from a seed

Answer 22

germinate

Question 23

What is the purpose of the steam in an endospore stain?

Answer 23

The steam forces the malachite green into the endospores

Question 24

What stains are used in an endospore stain?

Answer 24

Primary stain- malachite green (forced into the spores by heat)
Decolorization-water (removes stain from cells, but not spores)
Counterstain- safranin

Question 25

What color is the endospore and vegetative cells after staining in an endospore stain?

Answer 25

Endospore- green

Vegetative cell- red

Question 26

What genera produce spores?

Answer 26

Bacillus and Clostridium

Question 27

Which culture would have more spores: 24 hr culture OR 72 hr culture?

Answer 27

A 72 hour culture