Microbial Mechanisms of Pathogenicity

Question 1

What is the term for a change from a state of health?

Answer 1

Disease

Question 2

What is the term for a disease caused by a pathogen?

Answer 2

Infectious disease

Question 3

Name 4 things a microbe must do in order to cause disease

Answer 3

1. Access the host
2. Adhere to the host
3. Penetrate/evade the host’s defenses
4. Damage host tissues

Question 4

What is the most important determinant of disease initiation and outcome?

Answer 4

Host immunity

Question 5

What is the term for the ability of a microbe to cause disease in a host cell?

Answer 5

Pathogenicity

Question 6

What is the term for the relative degree of pathogenicity?

Answer 6

Virulence

Question 7

What is the term for the place a microbe enters a host?

Answer 7

Portal of entry

Question 8

What 3 portals of entry are specific to females?

Answer 8

Mammary glands, vagina, and placenta

Question 9

What is the most frequently used portal of entry?

Answer 9

Respiratory tract

Question 10

What is the term for the membranes that line the body cavities that open to the outside?

Answer 10

Mucous membranes

Question 10

Name 3 microbes that can cross the placenta

Answer 10

T. pallidum, HIV, and T. gondii

Question 11

Why is unbroken skin a good barrier against infection?

Answer 11

Lots of layers

Question 12

What is the term for the portal of entry in which there is a break in the skin?

Answer 12

Parenteral route

Question 13

Insect bites would be transmitted via what portal of entry?

Answer 13

Parenteral route

Question 14

What is the term for the number of microbes that are first introduced to the host?

Answer 14

Infecting dose

Question 15

What is the term for the dose of microbes that if infected would cause disease in 50% of the population?

Answer 15

ID50

Question 16

What is the term for the dose of microbes that if infected would cause death in 50% of the population?

Answer 16

LD50

Question 17

What is the term for the parts of a bacterial cell wall that help it survive the normal flow inside the body?

Answer 17

Adhesins

Question 18

The majority of adhesins are made of

Answer 18

Proteins

Question 19

What are 4 components of bacteria that help them evade phagocytosis?

Answer 19

Capsules, lipopolysaccharides (LPS), mycolic acid, and slime layers

Question 20

What two types of human cells help kill bacteria?

Answer 20

Neutrophils and macrophages

Question 21

What type of bacterial cell wall contains lipopolysaccharides?

Answer 21

Gram-negative bacteria

Question 22

What is the enzyme that causes coagulation?

Answer 22

Coagulase

Question 23

What is the enzyme that helps break up clots?

Answer 23

Fibrinolysin

Question 24

What is the enzyme that breaks down hylauronic acid?

Answer 24

Hyaluronidase

Question 25

What is the enzyme that breaks down collagen?

Answer 25

Collagenase

Question 26

What is the enzyme that breaks down IgA antibodies?

Answer 26

IgA protease

Question 27

What is a bacterium that uses hyaluronidase and collagenase to cause gas gangrene?

Answer 27

C. perfringens

Question 28

What is the term for a microbe changing its appearance so that the host’s immune system does not recognize it?

Answer 28

Antigenic variation

Question 29

What type if viruses often do antigenic variation?

Answer 29

RNA viruses

Question 30

What is the term for the movement of a membrane that allows bacteria to pass through human cells?

Answer 30

Membrane ruffling

Question 31

What protein do bacteria cells make that helps them rearrange the host’s membrane?

Answer 31

Invasin

Question 32

What are 2 bacteria that produce and use invasion?

Answer 32

Salmonella and E. coli

Question 33

What is the term for something made by bacterial cells that collects free iron?

Answer 33

Siderophores

Question 34

What is the term for a toxin that is released into the environment?

Answer 34

Exotoxin

Question 35

What is the term for that is released from the outer membrane of a cell?

Answer 35

Endotoxin

Question 36

What is the term for exotoxins that attack nerves?

Answer 36

Neurotoxins

Question 37

What is the term for exotoxins that attack the intestine?

Answer 37

Enterotoxins

Question 38

What is one example of an enterotoxin?

Answer 38

Staphylococcal enterotoxin

Question 39

What is the term for a membrane disrupting exotoxin that attacks phagocytic white blood cells?

Answer 39

Leukocidin

Question 40

What is the term for an exotoxin that causes hemolysis of red blood cells?

Answer 40

Hemolysin

Question 41

What is the term for something that can cause a fever?

Answer 41

Pyrogens

Question 42

What are 3 side effects of endotoxins?

Answer 42

Fever, shock, miscarriage

Question 43

What condition is characterized by abnormal clotting all over the body and is cause by endotoxins?

Answer 43

Disseminated intravascular coagulation

Question 44

What is the test performed to test for endotoxins?

Answer 44

LAL (limulus amoebocyte lysate assay)

Question 45

What is the term for responses of your immune system that damage itself?

Answer 45

Hypersensitivity reactions

Question 46

What is one example of a microbe that causes hypersensitivity reactions?

Answer 46

S. pyogenes

Question 47

What are 5 portals of exit for a microbe?

Answer 47

1. Respiratory
2. Feces
3. Genitourinary
4. Skin
5. Transplacental

Question 48

What is the term for marking a microbe to be destroyed by the immune system?

Answer 48

Opsonization