Microbial Factors Contributing To Phatogenesis And Virulence

Question 1

Mechanism by which the disease is caused.

Answer 1

Pathogenesis

Question 2

Ability of a microbe to produce disease in susceptible individual l.

Answer 2

Pathogenicity

Question 3

Two types of pathogens.

Answer 3

True/frank pathogen
Oppurtunistic pathogen

Question 4

This type of pathogen can be recognized to cause disease in healthy immunocompetent individual.

Answer 4

True pathogens

Question 5

Common bacterial species of true pathogen.

Answer 5

Yersinia pestis
Bacillus anthracis

Question 6

Due to invasive medical procedures against diseases, patients become more____.
A. Susceptible to infection
B. Less susceptible in infection
C. Normal flora is seen increasing in causing infection to immunocompromised individuals
D. All of the above.

Answer 6

A and C

Question 7

Examples of opportunistic pathogens.

Answer 7

Haemophilus influenzae
Staphylococcus epidermidis

Question 8

An opportunistic pathogen that is life threatening in human.

Answer 8

Haemophilus influenzae

Question 9

An oppurtunistic pathogen that can infect in patient with prosthetic devices

Answer 9

Staphylococcus epidermidis

Question 10

An infection that occurs as the result of medical treatment or procedures.

Answer 10

Iatrogenic infection

Question 11

T or F
Indwelling urinary catheters develop what?

Answer 11

Urinary tract infection

Question 12

T or F
Patients with immunosuppresisve drugs after transplant are resistant in infections.

Answer 12

False- they are susceptible

Question 13

Is the relative ability of microorganisms to cause disease or the degree of pathogenicity.

Answer 13

Virulence

Question 14

T or F
Organisms that can establish low infective dose are more virulent than organisms that require high no. of infection.

Answer 14

True

Question 15

T or F
Shigella causd disease with relatively low infective dose.

Answer 15

True (100 organisms)

Question 16

These are mechanisms that allow bacteria to persist in host amd cause disease.

Answer 16

Microbial virulence factors

Question 17

These allow the pathogen to evade or overcome host defenses.

Answer 17

Virulence factors

Question 18

Examples of virulence factors.

Answer 18

• inhibiting phagocytosis
• adhesion to host cells/tissue
• enhacing intracellular survival after phagocytosis
• damage tissue through production of toxins and extracellular enzymes

Question 19

T or F
Capsules and toxins are common virulence factors of bacteria.

Answer 19

True

Question 20

Which is not true about the defined virulence factor of a bacteria?
A. Diptheria and Cholera toxins
B. Capsule of streptococcus pneumoniae
C. Fimbriae of N. gonorrhoeae
D. Pili of Staphylococcus epidermidis

Answer 20

D

Question 21

Examples of phagocytic cells.

Answer 21

Macrophages
Polymorphonuclear cells

Question 22

What is the extremely important event in the life of invading pathogen and survival rate is to _____.

Answer 22

Avoid phagocytosis

Question 23

Common mechanism for evading phagocytosis.

Answer 23

Polysaccharide capsules

Question 24

Species of bacteria that are highly virulent through polysaccharide capsule.

Answer 24

S. pneumoniae
H. influenzae

Question 25

T or F Capsule can be made by polysaccharide, protein, or combination.

Answer 25

Truee

Question 26

How does the capsule protect the pathogen from the immune response of host?

Answer 26

They mask the cell surface structure that can be recognized by the receptors of phagocytes.

Question 27

What is the concept of lipid A in escaping phagocytosis?

Answer 27

- it interferes with the binding of the host antibodies. - Antibodies bind to antigen through Fab/antigen-binfing portion - Protein A binds to Fc portion of IgG that prevents opsonization (markings).

Question 28

Streptococci produce___ that lyses RBCs. Staphylococci produce ____ that is toxic in WBCs

Answer 28

Hemolysins Leukocidins

Question 29

Staphylococcus release ____ that cause lysosomal discharge in cytoplasm.

Answer 29

Leukocidins

Question 30

Staphylococci leukocidins, called

Answer 30

Panton Valentine

Question 31

Lethal to WBCs and contributes to invasiveness of bacteria.

Answer 31

Panton Valentine

Question 32

This cause the host to less able direct the polymorphynuclear neutrophils (PMNs) and macrophages going to the site of infections.

Answer 32

Chemotaxis

Question 33

T or F Some diseases cause by exotoxins (botulism, staphylococcal) adhesion to cells/tissue is important.

Answer 33

False

Question 34

Cell surface structures that mediate atrachement are called?

Answer 34

Adhesins

Question 35

What is the main adhesins in bacteria,

Answer 35

Fibriae (pili) and surface polysaccharide

Question 36

Which is/are not true about fibriae in adhesion of the bacteria to the host? A. They can be resistanced to the host B. Increased the organisms' colonizing ability C. Phagocytosis is less likely to occur D. Replicates the bacterial cells

Answer 36

D

Question 37

Example of bacteria that uses fimbriae that adheres to the small intestine in which they release toxins to cause diarrhea.

Answer 37

Eschericia coli

Question 38

This bacteria uses fibriae to infecth epithelia cells of the genitourinary tract.

Answer 38

Gonococci (N. gonorrhoeae(

Question 39

How bacteria survive in intracellular activities in phagocytosis?

Answer 39

- From being resistanced to the effect of lysosomal content - escaping from phagosome

Question 40

Secretory antibodies produced ____ to protect against infection.

Answer 40

Lactoferrin Lysozyme

Question 41

It competes with bacteria for free iron.

Answer 41

Lactoferrin

Question 42

This genera of bacteria uses lactoferrin as a source of iron.

Answer 42

Meningocci

Question 43

T or F Non -pathogenic Neisseria spp. can be inhibited by the lactoferrin.

Answer 43

True

Question 44

This enzymes degrades IgA found at mucusal surface.

Answer 44

Immunoglobulin (IgA) proetease

Question 45

Pathogens that have immunoglobulin protease

Answer 45

H. influenzae, N. gonorrhoeae, N. meningitidis

Question 46

T or F Some pathogens circumvent host antibodies by shifting key cell surface antigens.

Answer 46

True

Question 47

Example of pathogens that can shift key cell surface antigen.

Answer 47

Influenza virus Borrelia spp.

Question 48

These species are easily engulfed by macrophages, but they can survive and multiply intracellularly.

Answer 48

Chlamydia Mycobacterium Brucella Listeria

Question 49

Pathogens exhibit an ability to penetrate and grows on tissue.

Answer 49

Invasion

Question 50

T or F Gonococcus organism is invasice they can infect the fallopian tube.

Answer 50

True

Question 51

T or F Salmonella spp. is invasive.

Answer 51

False- dissemination

Question 52

Pathogen spread infection to distant sites are called?

Answer 52

Dissemination

Question 53

Example of dissemination pathogen.

Answer 53

Corynebacterium diptheriae

Question 54

T or F Organisms that survive phagocytosis may be disseminated rapidly and the organisms are not invasive.

Answer 54

True

Question 55

Example of highly invasive species of bacteria.

Answer 55

Clostridium perfringens

Question 56

Disease from infection only noticeably only in tissue cause by ____.

Answer 56

Exotoxins and endotoxins

Question 57

These are poisonous subs. Produced by organisms that can disrupt metabolism and cause harm.

Answer 57

Toxins

Question 58

This type of toxins is produced by both gram + and - bacteiria.

Answer 58

Exotoxins

Question 59

Exotoxins can mediate the direct spread of microorganisms through ____.

Answer 59

Matrix of connective tissues.

Question 60

How does the bacteria spread in the matrix of connective tissue?

Answer 60

The bacteria produce substances like proteases and hyaluronidase that liquify the hyaluronic acid of the tissue.

Question 61

T or F Endotoxin is exclusive only in gram positive bacteria.

Answer 61

False (gram -)

Question 62

T or F Endotoxin has enzyme activity.

Answer 62

False

Question 63

What is the constituent of Endotoxins?

Answer 63

Lipopolysaccharide

Question 64

T or F Endotoxin can be destroyed by heating

Answer 64

False

Question 65

Two subunits of exotoxins

Answer 65

Nontoxic Toxic (bind toxin to the host cells)

Question 66

Toxin gene is encoded by phages, plasmids, transposons.

Answer 66

True

Question 67

Example of exotoxins bacteria. A. Clostridium difficile B. Diphtheria C. Botulinum D. Salmonella

Answer 67

A,B,C

Question 68

This exotoxin bacteria inhibits protein synthesis and affects the heart, nerve tissue, liver.

Answer 68

Diptheria toxins

Question 69

It is a neurotoxin that blocks nerve impulse transmission and can cause flaccid paralysis especially in infant.

Answer 69

Botulinum toxin

Question 70

They produce exfoliatin that can cause rash and massive skin peeling.

Answer 70

Streptococcus pyogenes S. aureus

Question 71

Endotoxins composed of LPS on the ___ of gram negative bacteria.

Answer 71

Outer membrane

Question 72

3 regions of LPS In gram negstive.

Answer 72

Antigenic O-specific polysaccharide Core polysaccharide Inner lipid A

Question 73

Which is not the effect of LPS in the body? A. Changes in bp, clotting B. Change in body temp., metabolism C. Damage Body Immunity D. Change in pH of blood and urine

Answer 73

D.

Question 74

The toxic activity of endotoxin is found in ___.

Answer 74

Inner lipid A

Question 75

Endotoxins stimulate the fever in the center of ___.

Answer 75

Hypothalamus

Question 76

Increase in body temp: Severe hypotension:

Answer 76

- 1 hour - 30 mins

Question 77

Effect of endotoxin that may be lethal.

Answer 77

Septic or endotoxic shock

Question 78

T or F Endotoxin can cause coagulation in blood.

Answer 78

True

Question 79

It occurs within a minute after exposure to endotoxin. Sequention of Neutrophils in the lungs mostly.

Answer 79

Sever neutropenia

Question 80

This follows neutropenia because neutrophils are released in bone marrow.

Answer 80

Leukocytosis