SCB 260 CHAPTER 15 MICROBIAL
MECHANISMS PATHOGENICITY ACTUAL
EXAMINATION 2026 QUESTIONS WITH
ANSWERS GRADED A+
⩥ Koch's Postulates. Answer: a sequence of experimental steps for
directly relating a specific microbe to a specific disease
⩥ Pathogens. Answer: Microbes that cause disease or tissue damage in a
host
⩥ Pathogenicity. Answer: ability to cause disease
⩥ Virulence. Answer: measure of pathogenicity
⩥ Opportunistic pathogen. Answer: causes disease only in the absence
of normal host resistance
⩥ Infection. Answer: Situation in which a microorganism is established
and
growing in a host, whether or not the host is harmed
, ⩥ Disease. Answer: damage or injury to the host that impairs host
function
⩥ Virulence. Answer: The relative ability of a pathogen to cause disease
⩥ How can virulence be measured. Answer: - Lethal dose 50% (LD50)
- Infectious dose 50% (ID50)
⩥ What is the LD50. Answer: Amount of an antigen that kills 50% of the
animals in a test group
⩥ Highly virulent pathogens show ______ difference in the number of
cell required to kills 100% of the population compared to 50% of the
population. Answer: Little
⩥ ID (infective dose). Answer: Minimum number of organisms required
to cause an infection in a host
⩥ Important entry point for pathogens. Answer: Mucosal surfaces
-most have a specific entry point
⩥ Infection process. Answer: 1. Exposure to pathogens
2. Adherence to skin or mucosa
MECHANISMS PATHOGENICITY ACTUAL
EXAMINATION 2026 QUESTIONS WITH
ANSWERS GRADED A+
⩥ Koch's Postulates. Answer: a sequence of experimental steps for
directly relating a specific microbe to a specific disease
⩥ Pathogens. Answer: Microbes that cause disease or tissue damage in a
host
⩥ Pathogenicity. Answer: ability to cause disease
⩥ Virulence. Answer: measure of pathogenicity
⩥ Opportunistic pathogen. Answer: causes disease only in the absence
of normal host resistance
⩥ Infection. Answer: Situation in which a microorganism is established
and
growing in a host, whether or not the host is harmed
, ⩥ Disease. Answer: damage or injury to the host that impairs host
function
⩥ Virulence. Answer: The relative ability of a pathogen to cause disease
⩥ How can virulence be measured. Answer: - Lethal dose 50% (LD50)
- Infectious dose 50% (ID50)
⩥ What is the LD50. Answer: Amount of an antigen that kills 50% of the
animals in a test group
⩥ Highly virulent pathogens show ______ difference in the number of
cell required to kills 100% of the population compared to 50% of the
population. Answer: Little
⩥ ID (infective dose). Answer: Minimum number of organisms required
to cause an infection in a host
⩥ Important entry point for pathogens. Answer: Mucosal surfaces
-most have a specific entry point
⩥ Infection process. Answer: 1. Exposure to pathogens
2. Adherence to skin or mucosa
