5.1: Microbial infection

Question 1

What is the classification of viruses?

Answer 1

not cells in their own right

Question 2

What is the classification of bacteria?

Answer 2

prokaryotes

Question 3

What is the classification of fungi?

Answer 3

eukaryotes- single cell

Question 4

What is the classification of protozoa?

Answer 4

eukaryotes- single cell

Question 5

What is the classification of helminths

Answer 5

eukaryotes- multi-cellular

Question 6

What is another word for viruses?

Answer 6

obligate parasites

Question 7

What is the genetic material contained in viruses?

Answer 7

RNA or DNA

Question 8

Do viruses show host specificity?

Answer 8

yes

Question 9

How do viruses divide?

Answer 9

by budding out of host cells or cytolysis

Question 10

What are the routes of infection of a virus?

Answer 10

various routes

faecal-oral, airborne, insect vectors, blood borne

Question 11

What is an example of a retrovirus?

Answer 11

HIV– enveloped virus
‘DNA makes RNA makes protein’
RNA genome requires reverse transcriptase

Question 12

What is the only infectious disease to be eradicated by vaccination?

Answer 12

smallpox (variola virus)

Question 13

What is the human papilloma virus?

Answer 13

virus that causes cervical cancer

Question 14

What is the structure of prokaryotes?

Answer 14

they do not have internal membranes

photosynthetic bacteria are an exception

Question 15

How is the genetic material contained in prokaryotes?

Answer 15

single copy of a chromosome
(haploid)

eukaryotes can be haploid or diploid

Question 16

Do prokaryotes have a cytoskeleton?

Answer 16

yes

but it is poorly defined unlike eukaryotes where it is well developed

Question 17

What does prokaryote cell wall contain?

Answer 17

peptidoglycan

Question 18

How do prokaryotes divide?

Answer 18

binary fission

Question 19

What are the key structures of bacteria?

Answer 19

pilus, capsule, cell wall, plasma membrane, nucleoid (DNA), cytoplasm, ribosomes

Question 20

What are pili used for?

Answer 20

determine how cells interact with and adhere to surfaces

Question 21

What is the role of the capsule?

Answer 21

can prevent desiccation or hinder phagocytosis

Question 22

What is the role of the flagella?

Answer 22

important for swimming

Question 23

What is shigella?

Answer 23

an invasive pathogen

faecal-oral transmission

Question 24

What is neisseria meningitidis?

Answer 24

a commensal pathogen that lives without causing harm in the naso-pharynx of about 20% of population
causes: rash, septicaemia
penetrates cerebrospinal fluid- meningitis

Question 25

What are hospital acquired infections?

Answer 25

``` antimicrobial resistance (AMR) c. difficile and MRNA ```

Question 26

What is helicobacter pylori

Answer 26

causes peptic ulcer and gastric cancer

Question 27

How do pathogens evolve so quickly?

Answer 27

mutation rates

Question 28

Mutations in viruses

Answer 28

have error-prone replication and they dont correct the errors they make with very high efficiency

Question 29

mutations in bacteria

Answer 29

are haploid so only one gene needs to be mutated to have any phenotypic effect - much shorter replication times (genes can be selected and spread in a population much more rapidly than in humans)

Question 30

What are the 3 groups of fungi?

Answer 30

cause cutaneous, mucosal and/or systemic m

Question 31

What do fungi occur as?

Answer 31

yeasts, filaments or both | filaments have cross walls or septa

Question 32

How do fungi replicate?

Answer 32

bud or divide

Question 33

What are protozoa?

Answer 33

unicellular eukaryotic organisms | intestinal, blood and tissue parasites

Question 34

How do protozoa replicate?

Answer 34

by binary fission or by formation of trophozoites inside a cell

Question 35

How is infection by protozoa acquired?

Answer 35

ingestion or through a vector eg insect or invertebrate vector

Question 36

What are examples of protozoa?

Answer 36

malaria and laishmaniasis

Question 37

What is malaria?

Answer 37

plasmodium species - infection is acquired via a mosquito vector - blood and tissue parasites - formation of trophozoites inside a cell

Question 38

What is leishmaniasis?

Answer 38

Leishmania species - infection is acquired via a sandfly vector - blood and tissue parasites - formation of trophozoites inside a cell

Question 39

What are helminths?

Answer 39

metazoa with eukaryotic cells ( they contain cells that are differentiated into tissues and organs) - multi-cellular

Question 40

What is the life cycle of helminths?

Answer 40

outside the human host

Question 41

What are some examples of helminths?

Answer 41

roundworms flatworms tapeworms

Question 42

some flukes require hosts for life cycles

Answer 42

schistosomiasis

Question 43

What does effective treatment of infectious disease require?

Answer 43

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

Question 44

prevent

Answer 44

vaccination

Question 45

treat

Answer 45

drugs