Microbial Infection

Question 1

What are the five main types of infectious agents?

Answer 1

Viruses, fungi, helminths, Protozoa and bacteria

Question 2

What is the definition of a virus?

Answer 2

A obligate parasite
They are not ells in their own right
They contain RNA or DNA as genetic material

Question 3

How do viruses reproduce?

Answer 3

By infecting a host cell and using their nuclear synthetic machinery

Question 4

What can viruses infect?

Answer 4

All life forms, including bacteria
But they show host specificity

Question 5

How do viruses divide?

Answer 5

by budding out of host cell, or cytolysis

Question 6

What are some routes of infection for viruses?

Answer 6

various routes of infection
e.g., faecal-oral, airborne, insect vectors, blood borne

Question 7

What does HIV (retrovirus) RNA genome require?

Answer 7

reverse transcriptase

Question 8

What was used to treat polio virus?

Answer 8

Pressure machines, to make it easier to breath

Question 9

What virus can cause cervical cancer?

Answer 9

papilloma virus

Question 10

What type of cells are bacteria?

Answer 10

Prokaryotes

Question 11

DO prokaryotes and eukaryotes have internal membranes?

Answer 11

No, photosynthetic bacteria are an exception

Eukaryotes have internal membranes that define organelles including nucleus, ER, mitochondria

Question 12

Are prokaryotes/ eukaryotes haploid or diploid?

Answer 12

prokaryotes are haploid (single copy of chromosome)
eukaryotes can be haploid or diploid

Question 13

What type of organisms are fungi?

Answer 13

Eukaryotes - Single cell

Question 14

What type of organisms are protozoa?

Answer 14

Eukaryotes - single cells

Question 15

What type of organisms are helminths?

Answer 15

Eukaryotes - multicellular

Question 16

What type of genetic material do viruses contain?

Answer 16

RNA or DNA

Question 17

What is an example of a virus and what type f genetic matter does it have?

Answer 17

HIV - Is a retrovirus so has RNA

Question 18

what is the difference between eukaryotes and prokaryotes?

Answer 18

Prokaryotes do not have internal membranes and therefore do not have membrane bound organelles

Question 19

What is the difference in cytoskeleton between eukaryotes and prokaryotes?

Answer 19

Prokaryotes cytoskeleton is poorly defined.
Eukaryotic cells have well developed cytoskeleton

Question 20

What does the prokaryote cell wall contain?

Answer 20

Peptidoglycan

Question 21

How do prokaryotes divide?

Answer 21

Binary fission

Question 22

What structure of bacteria allows them to move?

Answer 22

Flagellum

Question 23

What type of DNA do bacteria have?

Answer 23

Double stranded DNA

Question 24

How does Shigella spread?

Answer 24

Faecal-oral transmission

Question 25

How does shigella spread from cell to cell?

Answer 25

invades and destroys the cell by using host cell actin

Question 26

Which bacteria causes meningitis?

Answer 26

Neisseria Meningitidis - when it infects the CSF

Question 27

What is the result of septicaemia on the body?

Answer 27

Rapid progression, septic shock and a severe inflammatory response

Question 28

How would you describe Neisseria meningitidis?

Answer 28

community acquired (multiple serogroups) commensal to pathogen

Question 29

What is another way to say hospital-acquired?

Answer 29

nosocomial

Question 30

Which bacteria are commonly responsible for hospital acquired infections?

Answer 30

Clostridium difficile (forms spores which are hard to remove) Methicillin Resistant Staphylococcus Aureus

Question 31

Which bacteria causes peptic ulcers and gastric cancer?

Answer 31

Helicobacter pylori

Question 32

How is mycobacterium tuberculosis spread?

Answer 32

Airborne

Question 33

What is the top infectious killer in the world?

Answer 33

tuberculosis

Question 34

How do bacteria evolve so quickly?

Answer 34

They have similar mutation rates to humans, however have a much shorter generation time - therefore reproduce much more often, so more mutations when the generation time is shorter

Question 35

What three types of conditions can fungi cause?

Answer 35

Cuteanous, Mucosal or systemic mycoses

Question 36

How do fungi occur as?

Answer 36

Yeasts, filaments or both

Question 37

How do yeasts replicate?

Answer 37

They bud or divide

Question 38

What is a cutaneous infection?

Answer 38

skin

Question 39

What is an example of an infectious fungi?

Answer 39

CANDIDA ALBICANS

Question 40

What are two characteristic features of filaments?

Answer 40

They have cross walls or septa

Question 41

What do protozoa include?

Answer 41

Unicellular eukaryotic organisms - include intestinal, blood and tissue parasites

Question 42

How do protozoa replicate?

Answer 42

replicate in the host by binary fission or by formation of trophozoites inside a cell

Question 43

How is a protozoa infection acquired?

Answer 43

infection is acquired by ingestion or through a vector e.g., malaria and leishmaniasis

Question 44

How many hosts does the protozoa life cycle involve?

Answer 44

2

Question 45

Where can protozoa pathogens be found?

Answer 45

intestines, blood and tissue

Question 46

How does the pathogen which causes malaria replicate?

Answer 46

Forms trophozoites inside the host cell

Question 47

How is Malaria infection acquired?

Answer 47

Thrugh a mosquit vector

Question 48

What is the malaria belt?

Answer 48

The belt around the equator line in which the incidence of malaria is the highest - corresponds with high temperatures

Question 49

How does malaria replicate?

Answer 49

it is a blood and tissue parasite, by formation of trophozoites inside a cell

Question 50

What condition does Leishmania species cause?

Answer 50

LEISHMANIASIS

Question 51

How is Leishmaniasis infection acquired?

Answer 51

Via sandfly vector

Question 52

How does the Leishmania species replicate to cause Leishmaniasis?

Answer 52

Formation of trophozoites inside a cell

Question 53

What are helminths?

Answer 53

metazoa with eukaryotic cells

Question 54

Are helminths visible to the naked eye?

Answer 54

Yes; multi-cellular

Question 55

What are three examples of helminths?

Answer 55

Roundwords e.g., ascaris Flatworms (flukes) Tapeworms

Question 56

What type of transmission do helminths exhibit?

Answer 56

Faecal-oral transmission

Question 57

What disease do flukes cause?

Answer 57

Schistosomiasis

Question 58

Where is the lifecycle of helminths?

Answer 58

outside the human host

Question 59

What is a major health priority?

Answer 59

developing new strategies to prevent (vaccines) and treat (drugs) infection

Question 60

What does effective treatment require?

Answer 60

knowledge of the causative agent - its source and means of transmission - how they cause damage and how the human body reacts