Microbiology

Question 1

*Eukaryotes vs. Prokaryotes

Question 2

Bacteria - main structures

Question 3

Bacteria - accessory structures

Question 4

*Cell wall is rigid because… (+)
(Different from fungi and plants)

Question 5

Layers of cell wall (outer, inner, middle)

Question 6

•Peptidoglycan/Mucopeptides:

Answer 6

(Inner layer, rigid)

Question 7

•Lipopolysaccharides (+contains):

Answer 7

(Outer layer, non rigid)

Question 8

Teichoic acids types: (2)

Question 9

Lipoproteins:

Question 10

*Functions of bacteria cell wall:

Question 11

*Chemical structure of bacteria cell wall:

Question 12

•Bacteria cytoplasm membrane:

Answer 12

• AKA ‘osmotic barrier’
• non rigid
  -semi permeable
• (cell can/cannot survive?)

Question 13

**Functions of bacteria cytoplasmic membrane:

Question 14

•Bacteria Cytoplasm

Answer 14

• granular structure, contains nuclear material (associated with life cycle of cell)
• Granules (60% RNA, 40% proteins)

Question 15

What is responsible for protein synthesis?

Answer 15

Ribosomes
+ also production of enzymes involved in cell metabolism

Question 16

(Cytoplasm) Volutin granules:

Answer 16

• food and energy storage
• Larger granules

Question 17

(Cytoplasm) Nuclear materials:

Answer 17

• chromatin bodies (made of DNA)
• has coded info fro protein synthesis

Question 18

•Mesosomes:

Answer 18

Invaginations of cytoplasmic membrane bound/connected to the membrane

Question 19

•Pili/Fimbriae

Answer 19

• external hair like structures on bacteria cell
• mostly seen in Gram Negative

Question 20

Functions of Fimbriae/pili:

Answer 20

-adhesion of bacteria to surfaces
-adhesion to red cells (hemagglutination)
*- Is first step to Pathogenicity

Question 21

•Capsule

Answer 21

• Is Hydrophilic gel like structure
• not essential to bacteria life
• thicker but less dense than cell wall

Question 22

Functions of Capsule:

Answer 22

-Protection against Phagocytosis (cell eating)
-responsible for ‘mucoid colonies’
-can help in adherence

Question 23

•Flagella

Answer 23

• external thread like structure on bacteria cell
• arise from cytoplasmic membrane

(Inner ring: rotates)
(Outer ring: minimize friction & leakage)

Question 24

*Types of Flagella:

Question 25

•Bacterial Spore

Answer 25

• are structures formed at a vegetative state
  -they are resistant to heat, dehydration, or chemical disinfection

Non-sporing cell = Vegetative

Question 26

Structures of Bacterial Spores:

Answer 26

• Outer Coat (roughly 2-4 layers)
• Cortex (in the centre)
• Spore Wall (within Cortex)
• Spore Core (within Spore Wall, has DNA)

Question 27

Shape & Position of Spore:

Answer 27

Shape:
- Round
- Oval
- Cylindrical

Position:
- Central
- Terminal
- Subterminal

Question 28

Gram Positive (cell wall)

Question 29

Gram Negative (cell wall)

Question 30

Bacteria classification by Morphology/Shape

Answer 30

1. Coccus/Spherical
2. Rods
3. Filamentous
4. Spiral

Question 31

Bacteria Coccus/Spherical types:
(+ examples)

Question 32

Bacteria Rods types:
(+ examples)

Answer 32

• Straight rods ex. Bacilli
• Curved rods ex. Vibrio

Question 33

Bacteria Filamentous types:

Answer 33

• Actinomyces

Question 34

Bacteria Spiral types:

Answer 34

• Spirillum
• Spirochaetes

Question 35

Bacteria classification by Temperature:

Answer 35

• Thermophilic: 45° - 80°, Best at 50°
• Mesophilic:

Question 36

Which bacteria temp. is Pathogenic

Answer 36

Mesophilic bacteria (37°) is pathogenic because its at the human body temp.

(Pathogenic- bacteria that cause disease)

Question 37

*Plasmolysis DEF

Question 38

*Plasmoptysis DEF

Question 39

Carbohydrates metabolism AKA

Answer 39

Fermentation

Question 40

• End products of carbohydrates metabolism: (3)

Answer 40

-

Question 41

• End product of Protein metabolism…

Answer 41

Tissue damage

Question 42

• End product of Amino acids metabolism…

Answer 42

Can be helpful in identification of bacteria

Question 43

[Metabolism] Amino acids are produced by…

Answer 43

‘Proteolytic enzymes’

Question 44

• End product of nucleic acids

Answer 44

The liquefaction of ‘Purulent exudates’
(By enzymes DNase & RNase)

Question 45

Genetics DEF

Question 46

Which plasmid type is involved in pathogenicity?

Answer 46

Vi (incomplete)

Question 47

Types of Plasmid:

Question 48

Chromosomal elements: (2)

Question 49

Non chromosomal elements: (2)

Question 50

DNA DEF:

Question 51

RNA DEF

Question 52

Plasmid DEF

Question 53

Types of RNA:

Question 54

Types of Transposable elements:

Question 55

Phenotypic bacterial Variation..

Question 56

Genotypic bacterial Variation..

Question 57

Types of Genotypic variations:

Question 58

Mutation DEF + types:

Question 59

Classification of Mutation + DEF: (2)

Answer 59

1) Spontaneous mutations: happen in the absence of a know mutagen (during DNA replication)

2) Induced mutations: AKA mutagens, are agents in environment that causes mutations

Question 60

Types of Induced mutations:

Answer 60

• Light energy
  -Chemical energy

Question 61

Gene transfer DEF + types:

Question 62

Transformation DEF

Answer 62

Recipient cell takes up a fragment of Free DNA, from surrounding medium

Question 63

Conjunction DEF

Answer 63

Cell-to-Cell contact where DNA is transferred, by sex pili

Question 64

Transduction DEF

Answer 64

Transfer of fragments of DNA, by ‘bacterial viruses’