Question 1

Clostridium tetani

Accepted Answer

A)  TSS toxin 
B)  Heat-stable enterotoxin 
C)  Pneumolysin 
D)  Tetanospasmin

Question 2

Characteristics of exotoxins include (Select all that apply)

Accepted Answer

A)  They are produced by both Gram-positive and Gram-negative bacteria. 
B)  They are formed from a combination of proteins and lipids 
C)  Every exotoxin has a distinct chemical structure. 
D)  Every exotoxin damages host cells in a unique way.

Question 3

An example of a pathogen that avoids host defenses as shown is

Accepted Answer

A)  Rhinovirus 
B)  Chlamydia trachomatis 
C)  Mycobacterium tuberculosis 
D)  Haemophilus influenzae type b

Question 4

A pathogen that inhibits the immune system at the site marked V is

Accepted Answer

A)  Measles virus 
B)  Epstein Barr virus 
C)  HIV 
D)  Meningitis-causing bacteria

Question 5

ID50 refers to __________________________, while LD50 refers to _____________________________.

Accepted Answer

A)  infectious dose/lethal dose 
B)  number of microbes required to cause disease in 50% of test subjects/number of microbes required to cause death in 50% in 50% of test subjects. 
C)  number of sick test subjects/number of dead teste subjects 
D)  effectiveness of microbes to cause disease/effectiveness of microbes to cause death

Question 6

Why do influenza pandemics occur? (Select all that apply)

Accepted Answer

A)  a hybrid virus is produced by antigenic shift 
B)  no hosts have any previous immunity to the new hybrid produced by antigenic drift 
C)  worldwide events facilitate the movement of hosts from one continent to another 
D)  the human portion of a hybrid virus attacks cytotoxic T cells

Question 7

Blood may serve as a vehicle for which of these pathogens? (Select all that apply)

Accepted Answer

A)  Hepatitis B virus 
B)  Human Immunodeficiency Virus 
C)  coli 
D)  Varicella zoster virus

Question 8

Enterococcus faecalis

Accepted Answer

A)  alpha hemolysis 
B)  gamma hemolysis 
C)  beta-hemolysis 
D)  delta-hemolysis

Question 9

Which of the following are characteristics of common vehicle transmission (Select all that apply)

Accepted Answer

A)  common vehicle or medium needed to carry pathogen to new host 
B)  may lead to a very slow spread of pathogens to many people 
C)  examples of vehicles include food, air, water or blood 
D)  water may carry pathogens from wild animal population to human community

Question 10

What is the correct order of 5 steps in the process of pathogenesis?
V. microbes enter the host
W. cause damage
X. adhere to host tissues
Y. avoid destruction by host defenses
Z. exit host to continue chain of transmission

Accepted Answer

A)  v ,w, x, y, z 
B)  v, x, y, w, z 
C)  v, y, x, w, z 
D)  v, x, w, y, z

Question 11

There is an interplay of microbial and host factors that work in concert to promote a disease. What are the most important host factors you can have to keep you well? (Select all that apply)

Accepted Answer

A)  genetic factors 
B)  inflammatory response and fever 
C)  health status and prior immunity 
D)  physical and chemical defenses

Question 12

The natural habitat or host of pathogen until it finds a new host

Accepted Answer

A)  Pathogenesis 
B)  Reservoir 
C)  Communicable pathogens 
D)  Noncommunicable pathogens

Question 13

The ID50 for a Listeria infection shown is

Accepted Answer

A)  3.1 
B)  1300 
C)  10,000 
D)  1100

Question 14

Streptococcus pneumoniae

Accepted Answer

A)  alpha hemolysis 
B)  gamma hemolysis 
C)  beta-hemolysis 
D)  delta-hemolysis

Question 15

Which of the following is a biological vector?

Accepted Answer

A)  house fly 
B)  cockroach 
C)  tick 
D)  ant

Exam 16: Microbial Pathogenesis