W3-3 Bacteria pathogenesis

Question 1

What is the LD50 of a pathogen?

Answer 1

the amount required to kill 50% of organisms (measures virulence)

Question 2

Extoxin

Answer 2

secreted from bacteria to affect host somewhere else

Question 3

Endotoxin

Answer 3

intrinsically part of host, but removed and secreted to host for toxic effects

Question 4

Hemolysis test: tests for what type of toxicity?

Answer 4

extoxins: cytolytic

Question 5

Three possible results of hemolysis test

Answer 5

α: partial hemolysis, leaves green edge

β: total hemolysis, large missing area

γ: culture grows but no hemolysis

Question 6

Describe AB toxins: type and action

Answer 6

Type: exotoxins

Action: B unit Binds to host cell and A unit carries out toxic Action

Question 7

Flacid paralysis cause and example

Answer 7

Inhibits ACh at NMJ

botulism

Question 8

Spacstic paralysis cause and example

Answer 8

inhibits glycine release on inhibitory neuron, does not allow relaxation

tetanus

Question 9

What is a super antigen?

Answer 9

One that stimulates the specific immune system more than it should in a nonspecific manner. Leads to large amounts of inflammation

Question 10

What are the three parts of an endotoxin?

Answer 10

1. Lipid
2. Core polysaccharide
3. O-specific polysaccharide

Question 11

What is the toxic part of an endotoxin?

Answer 11

lipid

Question 12

What is the function of the O-specific polysaccharide of an endotoxin clinically?

Answer 12

unique to organism, identifiable in lab setting

Question 13

Which is more toxic: endotoxin or exotoxin?

Answer 13

exotoxin

Question 14

3 types of hypersensitivity immune responses

Answer 14

T1: allergy

T2: antibodies against pathogen also attack host

T3: WBCs pull pathogens out of tissue to attack in dangerous areas like capillaries

Question 15

The innate immune system counts on these molecules to be present on pathogens

Answer 15

PAMPs–pathogen associated molecular patterns

Question 16

These protein components of serum may bind to pathogens and help facilitate their phagocytosis

Answer 16

complement components

Question 17

Interferons

Answer 17

mediate early cellular response to viral infections

Question 18

Differentiation of immune system cells

Answer 18

a

Question 19

These cells respond immediately to infection

Answer 19

macrophages

Question 20

These cells are recruited by mircophages at the beginning of infection

Answer 20

neutrophils

Question 21

What is the purpose of the complement system?

Answer 21

to control inflammation

Question 22

Interferons

Answer 22

Produced by infected cells to recruit immune cell response

Question 23

Which cells are responsible for initiating the adaptive immune response?

Answer 23

phagocytes from innate response

Question 24

Cells responsible for bringing antigens to T-cells

Answer 24

Antigent Presenting Cells

Question 25

Immune system produces these in response to antigens perceived as dangerous

Answer 25

antibodies

Question 26

Two types of immunity

Answer 26

Active: host body initiates an immune response

Passive: antibodies are transferred from another person (either transfusion or from mother)