Bacteriology

Question 1

Define a species

Answer 1

A fundamental ecological genetic unit, that are reproductively isolated

Question 2

What factors influence speciation in bacteria?

Answer 2

Fast generation times
Adaptive mutations
Horizontal gene transfer

Question 3

What way can you get horizontal gene transfer?

Answer 3

Transformation, transduction and conjugation

Question 4

What is transformation gene transfer?

Answer 4

Uptake of naked DNA by a bacteria

Question 5

What is transduction gene transfer?

Answer 5

Bacterial DNA transferred by a phage

Question 6

What is conjugation gene transfer?

Answer 6

DNA transfer between bacterial cells like plasmids

Question 7

What is a prophage?

Answer 7

When a bacteriophage inserts DNA into the bacteria DNA

Question 8

What is polyphasic taxonomy?

Answer 8

Done by consensus classification using phenotypic genotypes and phylogenic data.

Question 9

What is a biofilm?

Answer 9

Structured populations of microorganisms and they live within their own extracellular polymeric substances

Question 10

Biofilm characteristics?

Answer 10

High biodiversity
Retention of exoenzymes
Retention in nucleic acids
Increased antibiotic resistance

Question 11

Biofilm life cycle?

Answer 11

Reversible attachment, irreversible attachment, maturation (colony formation) maturation 2 (continuous biofilm), dispersion/sloughing off, transport of biofilm particles.

Question 12

What are biofilm particles called?

Answer 12

Flocs

Question 13

What is the EPS?

Answer 13

Extracellular polymeric substances

Question 14

What happens during reversible adhesion of biofilm?

Answer 14

They use long distance forces to hold them 5-20nm away from the surface. Little energy is needed to remove the biofilm

Question 15

What happens during irreversible adhesion?

Answer 15

Binding is mediated by polymer bridges. Specific adhesion/ receptor based processes

Question 16

What are the 3 main functions of the cytoplasmic membrane?

Answer 16

Selective permeability
Transport proteins
Major site or energy conservation/consumption

Question 17

What makes structure of cell wall?

Answer 17

Peptidoglycan rigid polysaccharide that forms a sheet around the cell connected by polymers

Question 18

What do gram-negative bacteria contain in their cell wall?

Answer 18

Peptidoglycan

Question 19

What is microbial locomotion?

Answer 19

Microbes using eg: flagella or has vesicles to move around their environment

Question 20

What are flagella?

Answer 20

Long thin appendages used to move a microbe they contain the protein flagellin

Question 21

What is a microbe with Atrichous flagella?

Answer 21

No flagella

Question 22

What is a microbe with monotrichous flagella?

Answer 22

Single flagella

Question 23

What is a microbe with lophotrichous flagella?

Answer 23

Mutliple flagella in the same place

Question 24

What is a microbe with Amphitrichous flagella?

Answer 24

Single flagella at each end

Question 25

What is a microbe with petritrichous flagella?

Answer 25

Numerous flagella around cell structure

Question 26

What is chemotaxis?

Answer 26

Movement of a motile cell up or down a concentration of a molecule towards a particular substance

Question 27

What is gliding chemotaxis?

Answer 27

Use of pilli for propulsion

Question 28

What is Twitching chemotaxis?

Answer 28

Involve pilli extending tethering and retracting to pull them along. Type 4 pilli

Question 29

What is swarming chemotaxis?

Answer 29

Rapid coordinated behaviour described as multi cellular

Question 30

What are fimbrae and pili?

Answer 30

Important adherence mechanisms. Two types conjugation (sex) pilli or type. 4