Microbiology - The Nature of Infection

Question 1

Why is infection important?

Answer 1

Increased antibiotic resistance. Practising doctors treat infection on a daily basis.

Question 2

What are the three domains of life?

Answer 2

Bacteria, archaea and eukaryotes.

Question 3

What does AMR stand for?

Answer 3

Antimicrobial resistance.

Question 4

What are the major groups of human pathogens?

Answer 4

Protozoa, fungi, bacteria and viruses.

Question 5

What examples of human pathogens are eukaryotes?

Answer 5

Protozoa and fungi.

Question 6

What examples of human pathogens are prokaryotes?

Answer 6

Bacteria.

Question 7

What are viruses?

Answer 7

Non - living small obligate parasites.

Question 8

What are protozoa?

Answer 8

Single celled animals.

Question 9

What are fungi?

Answer 9

Higher plant like organisms.

Question 10

What are bacteria?

Answer 10

Small, single celled prokaryotes.

Question 11

What are the characteristics of eukaryotes?

Answer 11

Compartmental, linear chromosomes, 80S ribosomes, no/flexible cell wall.

Question 12

What are the characteristics of prokaryotes?

Answer 12

Simple, single circular chromosome, 70S ribosomes, rigid cell walls and rapid cell cycle.

Question 13

What is a nucleoid?

Answer 13

Contains DNA and proteins and has no nuclear membrane.

Question 14

What does the inflow of protons allow the cytoplasmic membrane do?

Answer 14

Generate energy by the production of ATP.

Question 15

What is the main component that makes up the cell wall?

Answer 15

Peptidoglycan.

Question 16

What are the two types of cell walls?

Answer 16

Gram Positive and Gram Negative.

Question 17

What type of cell wall does Penicillin target?

Answer 17

Gram +ve and Gram -ve.

Question 18

What makes up Gram +ve?

Answer 18

Thick multi-layer PG.

Question 19

What makes up Gram -ve?

Answer 19

Outer membrane, periplasm and a thinner PG layer.

Question 20

What does LPS stand for?

Answer 20

Lipopolysaccharide.

Question 21

Where are LPS molecules situated in cell walls?

Answer 21

On the outer membrane in a Gram -ve, makes the outer membrane asymmetric.

Question 22

What cell wall does fimbriae have?

Answer 22

Gram +ve.

Question 23

What cell wall does pilus have?

Answer 23

Gram -ve.

Question 24

What happens during prokaryotic protein synthesis simply?

Answer 24

Make distinct proteins with co-transcription and is a target for antibiotics.

Question 25

What is the significance for understanding infection control for the cytoplasmic or PM?

Answer 25

Can use sonication and ethanol to target it.

Question 26

What is the significance for understanding infection control for the cell wall?

Answer 26

Can use penicillin and glycopeptides to target it.

Question 27

What is the significance for understanding infection control for the outer membrane and LPS?

Answer 27

Antibiotic uptake and inflammation.

Question 28

What is the significance for understanding infection control for the Chromosome?

Answer 28

Gyrases antibiotic target.

Question 29

What is the significance for understanding infection control for the ribosome?

Answer 29

Protein synthesis inhibitors.

Question 30

What is the significance for understanding infection control for the pili, fimbriae and flagella?

Answer 30

Attachment, motility, invasion, sex and pathology.

Question 31

What food do prokaryotes need to grow?

Answer 31

Organic/inorganic C source, O H and N source, vitamins and trace elements e.g. Zn.

Question 32

What conditions do prokaryotes need to grow?

Answer 32

The optimal temperature e.g. mesophiles need body temp.
H ion conc. e.g. Human commensals pH 6.8-7.2.
Osmotic protection. e.g. Human commensals 0.85% NaCl.
O2 e.g. aerobes, microaerophiles, facultative and obligate anaerobes.

Question 33

What are the 4 phases of the bacterial growth curve?

Answer 33

Lag phase
Exponential phase
Stationary phase
Decline phase