Introduction To Microbes Flashcards Preview

[ ESA 3- Infection and Immunity > Introduction To Microbes > Flashcards

Flashcards in Introduction To Microbes Deck (106):
1

What categories can the microorganisms responsible for human disease be broken down into?

Viruses
Bacteria
Fungi
Parasites

2

Give an example of a virus?

Human Immunodeficiency Virus (HIV)

3

Give an example of a bacteria

Nisseria Meningitidis

4

Give an example of a fungi

Thrush

5

Give an example of a parasite

Plasmodium falciparum

6

What does plasmodium falciparum cause?

Malaria

7

What are viruses?

Obligate intracellular parasites without a cellular structure

8

What do viruses consist of?

Molecule(s) of either DNA or RNA (but not both) surrounded by a protein coat
May also have an envelope

9

What is a viruses envelope derived from?

The plasma membrane of the host cell from which its released

10

What do viruses do?

Hijack the host's mechanisms for creating mRNA and production of proteins to reproduce

11

What is the classification of viruses based on?

Their structure

12

What structural features can viruses be classified based on?

Single or double stranded
Enveloped or not
Positive or negative strand
Icosahedral or helical
DNA or RNA

13

Give an example of a single-stranded, non-enveloped DNA virus

Parvovirus 19

14

What can parvovirus 19 cause?

Mild infections in children
Fetal development issues in pregnant women

15

Give two examples of double-stranded, non-enveloped DNA viruses

Adenovirus
Human papilloma virus (HPV)

16

What can adenovirus cause?

Pharyngitis
Conjunctivitis
Infantile gastroenteritis

17

What does HPV induce?

Hyperplastic epithelial lesions of either cutaneous or mucosal epithelium

18

What do a small number of HPV virus types produce?

Lesions that have a risk of progressing to malignancy

19

Give an example of a malignancy that can arise from HPV infection

Cervical carcinoma

20

Give two examples of double-stranded, enveloped DNA viruses

Herpes
Hepatitis B

21

What are the types of herpes infections?

Primary HSV-1
Latent HSV-1
Primary HSV-2
Latent HSV-2

22

What can primary HSV-1 infections cause?

Tonsillitis and pharyngitis in adults
Gingivostomatitis in young children with ulcer forming usually in the oropharynx

23

What can latent HSV-1 infections cause?

'Cold sores' to appear on or around the lips

24

What can primary HSV-2 infections cause?

Lesions in the genital tract, similar to those found in the oropharynx in primary HSV-1 infections

25

What can latent HSV-2 infections cause?

Often asymptomatic

26

What does hepatitis B cause?

Acute hepatitis and later chronic liver disease

27

Give two examples of single-stranded, positive strand, icosahedral, non-enveloped RNA viruses?

Hepatitis A/E virus
Norovirus

28

How is hepatitis A/E most commonly spread?

Through fecally contaminated waters

29

What does the hepatitis A/E virus cause?

Hepatitis and impaired liver function

30

What is norovirus also known as?

The winter vomiting bug

31

What is norovirus the leading cause of?

Acute gastroenteritis

32

Where is norovirus common?

In closed environments, such as schools, hospitals, prisons, and cruise ships

33

Give 3 examples of single-stranded, positive strand, icosahedral or helical, enveloped RNA viruses

HIV
Hepatitis C
Rubella

34

How is HIV transmitted?

Sexually
Exchange of blood produces
Perinatally

35

How is HIV transmitted perinatally?

Transplacentally
During passage through the birth canal
By breastfeeding

36

What does HIV cause?

Acquired Immune Deficiency Syndrome (AIDS)

37

What does HIV and AIDS allow?

Increasingly frequent and serious opportunistic infections to occur

38

What does the hepatitis C virus cause?

Destruction of liver cells

39

How does the hepatitis C virus cause destruction of liver cells?

Through viral replication and host response

40

How hepatitis C transmitted?

Via the blood

41

How is the rubella virus spread?

Via respiratory secretions

42

What does the rubella virus result in?

German measles

43

What can the rubella virus cause in the developing fetus?

Extreme congenital defects

44

When can the rubella virus cause extreme congenital defects?

During the first trimester, when a pregnant woman is infected

45

Give four examples of single stranded, negative strand, helical, enveloped RNA viruses?

Ebola
Measles
Mumps
Influenza

46

How is the measles virus spread?

Respiratory droplets

47

What does the measles virus cause?

Fever
Cough
Eventually a rash

48

How is the mumps virus spread?

Respiratory droplets

49

What does the mumps virus cause?

Swelling of the parotid glands

50

How is influenza spread?

Respiratory droplets

51

What does influenza cause?

Fever
Muscle aches
Extreme drowsiness

52

Give an example of double-stranded, icosahedral, non-enveloped RNA virus

Rotavirus

53

What does rotavirus cause?

Severe viral gastroenteritis in infants and young children

54

What are bacteriophages?

A class of virus that infect bacteria

55

Where do bacteriophages play a key role?

Transmitting genetic material between different types of bacteria

56

What are true bacteria also known as?

Eubacteria

57

What kind of organisms are true bacteria?

Prokaryotic

58

What common structural organelles do most bacteria share?

Capsule
Cell wall
Plasma membrane
Cytoplasm
Ribosomes
Plasmid
Pili
Bacterial flagellum
Nucleoid (circular DNA)

59

Do all bacteria possess a capsule or flagellum?

No

60

What is the classification of bacteria based on?

Their overall shape identified under a microscope

61

What are the classifications of bacteria?

Coccus
Spirillus
Bacillus

62

What shape are cocci?

Circular

63

What shape are spirillus?

Spiral

64

What shape are bacillus?

Rods

65

How can cocci be arranged?

Clusters
Chains
Pairs

66

What is the bacterium called when it has cocci arranged in clusters?

Staph

67

What is the bacterium called when it has cocci arranged in chains?

Strep

68

What is the bacterium called when it has cocci arranged in pairs?

Diplo

69

What is used to help make bacteria visible under a light microscope?

A technique known as the Gram stain

70

What colour do gram positive bacteria appear with a gram stain?

Blue/violet

71

What colour do gram negative bacteria appear with a gram stain?

Red

72

What is whether a bacteria is gram negative or gram positive determined by?

The composition of its surrounding wall and membranes

73

What does the cell membrane of gram positive bacteria consist of?

Plasma membrane
Periplasmic space
Peptidoglycan

74

What does the cell membrane of gram negative bacterium consist of?

Plasma membrane
Periplasmic space
Peptidoglycan
Outer membrane

75

What does the outer membrane of gram negative bacterium consist of?

Lipopolysaccharide and protein

76

How does the cell membrane of a gram positive bacterium differ from a gram negative?

Thicker peptidolycan wall

77

What is the result of the thicker peptidoglycan wall of the gram positive bacterium?

Often causes host response

78

How can the cell wall of gram negative bacterium cause disease?

Present of lipopolysaccharides, which often acts as endotoxins

79

How do bacteria vary in their oxygen tolerance?

Aerobes can survive in the presence of oxygen, whereas anaerobes can survive in the absence of oxygen

80

What are obligate aerobes?

Bacteria that require oxygen to survive

81

What are obligate anaerobes?

Bacteria that require an oxygen free environment for survival

82

When can obligate anaerobes survive in an oxygen rich environment?

If they can form spores

83

On what characteristics can a bacteria be identified?

Gram staining
Shape
Arrangement

84

What can be done by identifying a bacterias characteristics?

Allows clinicians to narrow down the antimicrobials that should be used

85

Give 6 medically important gram positive cocci

Staph aureus
Coagulase negative staph
Alpha-haemolytic streptococci
Beta-haemolytic streptococci
Streptococcus pneumoniae
Enterococcus faecalis

86

Give an example of a beta-haemolytic streptococci

Strep pyogenes

87

Give 4 medically important gram negative cocci

Neisseria meningitidis
Neisseria gonorrhoeae
Moraxella catarrhalis
Acinetobacter baeumannii

88

Give 3 medically important gram positive bacilli

Listeria monocytogenes
Bacillus anthracis
Bacillus cereus

89

Give 6 medically important gram negative bacilli

Escherichia coli
Klebsiella pneumoniae
Proteus species
Salmonella typhi
Pseudomonas aeruginosa
Haemophilus influenzae

90

How do prokaryotes and eukaryotes differ in terms of chromosomes?

Prokaryotes are circular, usually single, and extra-chromosomal DNA may also be present (plasmids). Eukaryotes have multiple chromosomes

91

How do prokaryotes and eukaryotes differ in terms of their nucleus?

Prokaryotes have no nuclear envelope or nucleoli, whereas eukaryotes have membrane bound nucleoli present

92

How do prokaryotes and eukaryotes differ in terms of membrane-bound organelles?

Prokaryotes do not have them, whereas eukaryotes do

93

How do prokaryotes and eukaryotes differ in terms of cell wall?

Prokaryotes usually have a cell wall present, whereas eurkaryotes only have them in plant cells

94

What may the prokaryote cell wall contain?

Peptidoglycan

95

Do eukaryote cell walls have peptidoglycan?

No

96

How do prokaryotes and eukaryotes differ in terms of plasma membrane?

In prokaryotes, there is no carbohydrates and most lack sterols.
In eukaryotes, sterols and carbohydrates present

97

How do prokaryotes and eukaryotes differ in terms of ribosomes?

Prokaryotes have 70S ribosomes, eukaryotes have 80S (but 70S in organelles)

98

What are yeasts?

Single-celled fungi

99

Give three examples of yeasts

Candida albicans
Cryptococcus neoformans
Pneumocystis jiroveci

100

What are molds?

Multicellular fungi

101

Give two examples of molds

Aspergillus species
Dermatophytes

102

Give two examples of dematophytes

Ringworm
Athletes foot

103

What are protozoa?

Single celled parasites

104

Give 4 examples of protozoa

Giardia lamnbia
Cryptosporidium falciparum
Plasmodium falciparum
Typanosoma cruzi

105

What are helminths?

Multicellular parasites, worms

106

Give three examples of helminths

Roundworms
Tapeworms
Flukes