Question 1

Infectious dose of salmonella is:
A) 10
B) 100
C) 100000
D) 1000000

Accepted Answer

The infectious dose of Salmonella is typically around 100,000 bacteria, although it can vary depending on the strain and the host's immune system.

Question 2

Degree of pathogenicity:
A) Virulence
B) Infection
C) Transmission
D) Virulence factors

Accepted Answer

Virulence refers to the degree of pathogenicity or the ability of a microorganism to cause disease.

Question 3

specific bacterial surface proteins help entry into cells:
A) Invasins
B) Pili
C) Flagella
D) Capsule

Accepted Answer

Invasins are bacterial surface proteins that facilitate the entry of bacteria into host cells by interacting with the host cell's surface.

Question 4

One fact is false about exotoxins:
A) Usually produced by gram +ve bacteria
B) Diffusible
C) Immunogenic
D) Heat stable
E) Specific in action

Accepted Answer

Exotoxins are typically heat labile, meaning they are not heat stable and can be inactivated by heat.

Question 5

One fact is true about endotoxins
A) Produced by gram .ve bacteria
B) Strong immunogenic
C) Heat labile
D) Specific in action
E) Protein in nature

Accepted Answer

The answer of One fact is true about endotoxins
A) Produced...

Question 6

One fact is false about endotoxins
A) Produced by gram .ve bacteria
B) Produce fever
C) Can be converted to toxoids
D) Of chromosomal origin
E) Polysaccharide in nature

Accepted Answer

Endotoxins cannot be converted to toxoids. They are lipopolysaccharides, not proteins, and do not form toxoids like exotoxins can.

Question 7

Regarding stages of infection : period of invasion:
A) Time from initial contact with the infectious agents to the appearance of first symptoms
B) The earliest symptoms of infection appear as a vague feeling of discomfort, generalized body ache
C) The specific signs and symptoms exhibited by the patients according to the site of infection
D) The period of recovery.

Accepted Answer

The period of invasion is characterized by the specific signs and symptoms exhibited by the patient according to the site of infection.

Question 8

The presence of microorganisms in large numbers on a host tissue without host tissue damage:
A) Infection
B) Disease
C) Colonization
D) Transmission

Accepted Answer

Colonization refers to the presence of microorganisms on a host tissue without causing damage or disease to the host.

Question 9

Apparently healthy individuals carrying a pathogenic organism without showing clinical manifestations:
A) Infected
B) Carriers
C) True pathogens
D) Opportunistic pathogens

Accepted Answer

Carriers are individuals who harbor a pathogenic organism without exhibiting symptoms, potentially spreading the organism to others.

Question 10

Carriers are more serious that a case because:
A) They are confined to bed
B) They show manifestations
C) They communicate with public without being noticed
D) They carry the organism in the epidemic period
E) All of the above

Accepted Answer

Carriers are more serious than a case because they carry the organism in the epidemic period and communicate with the public without being noticed.

Question 11

Rarely cause disease in immune.competent people but can cause serious infections in immune.compromised patients:
A) True pathogen
B) Commensal
C) Flora
D) Opportunistic pathogen

Accepted Answer

Opportunistic pathogens are typically harmless in healthy individuals but can cause serious infections in those with weakened immune systems.

Question 12

Infection that has a worldwide distribution:
A) Epidemic
B) Pandemic
C) Endemic

Accepted Answer

A pandemic is an infection that spreads across multiple countries or continents, affecting a large number of people worldwide.

Question 13

Infection which is present at a low level in specific population
A) Epidemic
B) Pandemic
C) Endemic

Accepted Answer

An endemic infection is consistently present at a low level within a specific population or geographic area.

Question 14

All of the following are correct as regard exotoxin except:
A) It is protein
B) Heat stable
C) Secreted by both gram positive and gram negative
D) Can be changed into toxoid
E) Highly immunogenic

Accepted Answer

Exotoxins are typically heat-labile (not heat stable), meaning they can be inactivated by heat.

Question 15

All of following are correct as regard endotoxin except:
A) It is protein
B) It causes septic shock
C) It is part of cell wall of gram negative bacteria
D) Heat stable

Accepted Answer

Endotoxin is not a protein; it is a lipopolysaccharide found in the outer membrane of gram-negative bacteria.

Quiz 1: Pathogenesis-Antibiotic-Structure

Infectious dose of salmonella is:

Degree of pathogenicity:

specific bacterial surface proteins help entry into cells:

One fact is false about exotoxins:

One fact is true about endotoxins

One fact is false about endotoxins

Regarding stages of infection : period of invasion:

The presence of microorganisms in large numbers on a host tissue without host tissue damage:

Apparently healthy individuals carrying a pathogenic organism without showing clinical manifestations:

Carriers are more serious that a case because:

Rarely cause disease in immune.competent people but can cause serious infections in immune.compromised patients:

Infection that has a worldwide distribution:

Infection which is present at a low level in specific population

All of the following are correct as regard exotoxin except:

All of following are correct as regard endotoxin except: