Question 1

Which of the following is an example of an exotoxin?

Accepted Answer

Neurotoxins are exotoxins that are produced by bacteria and can cause damage to the nervous system.

Question 2

Which of the following is considered part of the indigenous microbiota of the female reproductive system?

Accepted Answer

The indigenous microbiota of the female reproductive system includes both Candida and Lactobacillus. Lactobacillus helps maintain a low pH environment that is protective, while Candida species can be found in small numbers without causing infection.

Question 3

Symptoms are

Accepted Answer

A

Question 4

Axenic systems of the body include

Accepted Answer

The kidneys are considered axenic, meaning they are free from microorganisms under normal conditions. Other areas like the nasal cavity, mouth, urethra, and conjunctiva of the eye typically have normal microbial flora.

Question 5

Which of the following is transmitted by the parenteral route?

Accepted Answer

Yellow fever is transmitted through the parenteral route, which means it is transmitted through non-oral means, such as through injection, transfusion, or other medical procedures that introduce the virus directly into the bloodstream. Ringworm, warts, gonorrhea, and cutaneous anthrax are all transmitted through other means, such as direct contact or inhalation.

Question 6

Among the virulence factors produced by Staphylococcus aureus are hemolysin, coagulase, hyaluronidase, and enterotoxin. Which of these factors contribute(s) to the ability of S. aureus to invade the body?

Accepted Answer

The answer of Among the virulence factors produced by Staphylococcus...

Question 7

A protozoan and its resident bacteria invade the body of a worm. The bacteria release toxins and exoenzymes that immobilize and digest the worm, and the protozoan and bacteria absorb the nutrients produced. The relationship between the protozoan and the bacteria would best be described as

Accepted Answer

The relationship between the protozoan and the bacteria is mutualism because both organisms benefit from the association; the bacteria help digest the worm, and both the protozoan and bacteria absorb the nutrients.

Question 8

Which of the following situations is NOT a way in which a baby acquires normal microbiota?

Accepted Answer

Microbes crossing the placenta during pregnancy is not a way in which a baby acquires normal microbiota. The other options all involve the acquisition of normal microbiota either through the birth process or through the introduction of microbes from the environment.

Question 9

Which of the following statements regarding the demonstration of the etiology of disease is FALSE?

Accepted Answer

The statement that the suspect agent must be the only potential pathogen present in disease cases is false. Many diseases can have multiple potential pathogens present, and it is possible for more than one microorganism to contribute to the development of a disease.

Question 10

Chagas' disease is transmitted by a bug with mouthparts that penetrate blood vessels. Which type of exposure does this represent?

Accepted Answer

The transmission of Chagas' disease through the bug's mouthparts that penetrate blood vessels represents the parenteral route, which involves the entry of pathogens directly into the bloodstream through a puncture or injection.

Question 11

A nosocomial disease is a disease acquired

Accepted Answer

A nosocomial disease is one that is acquired in a hospital or other healthcare facility. This can happen through contact with contaminated surfaces or objects, direct contact with infected individuals or exposure to airborne pathogens in the facility. Options A, B, and E are not exclusive to healthcare facilities, while option C explicitly refers to a specific mode of transmission.

Question 12

Mutualism is a relationship

Accepted Answer

Mutualism is a type of symbiotic relationship in which both members benefit from each other and sometimes one or both parties cannot survive without the other.

Question 13

Which of the following stages of an infectious disease is the most severe?

Accepted Answer

The illness period is the most severe stage of an infectious disease as this is when the individual experiences the most intense symptoms and the infection has reached its peak. During this stage, the body is actively fighting the infection, which can lead to symptoms such as fever, fatigue, and body aches. Depending on the disease, there may be complications that arise during the illness period, such as organ failure or pneumonia, which can be life-threatening.

Question 14

Which of the following situations might cause normal microbiota to become opportunistic pathogens?

Accepted Answer

Treatment with radiation can damage the immune system and disrupt the balance of normal microbiota, allowing them to become opportunistic pathogens.

Question 15

Diseases that are induced by modern medical procedures are referred to as

Accepted Answer

Iatrogenic infections are diseases or complications that occur as a result of medical treatment or procedures, including surgery, medication or exposure to medical devices. Examples include hospital-acquired infections and complications from surgery.

Question 16

Which of the following is a sign of disease?

Accepted Answer

A fever is an increase in body temperature and is often a sign of an underlying infection or disease. Headaches, dizziness, nausea, and cramps can be symptoms of various illnesses, but they can also be caused by other factors and are not necessarily indicative of disease on their own.

Question 17

Which of the following is considered a mechanical vector transmission?

Accepted Answer

Mechanical vector transmission refers to the passive transport of pathogens by an insect or other animal. The pathogen does not undergo any lifecycle changes within the vector. In the case of a cockroach transmitting Shigella, the cockroach can carry the pathogen on its body from feces or other contaminated sources to food or surfaces that humans then touch or consume, leading to infection. This is different from biological transmission, where the pathogen undergoes a lifecycle change within the vector, as seen in the other options.

Question 18

The fungus Pneumocystis jiroveci is found in the lungs of most people in low numbers, but in immunocompromised people it overgrows, resulting in severe respiratory problems. The fungus is best described as

Accepted Answer

Pneumocystis jiroveci is normally present in the lungs of healthy individuals, indicating that it is a part of the resident microbiota. However, in immunocompromised individuals, it can overgrow and cause severe respiratory problems, making it an opportunistic pathogen. Therefore, the best choice is E, both resident microbiota and opportunistic pathogen.

Question 19

Which of the following is NOT an example of symbiosis?

Accepted Answer

The answer of Which of the following is NOT an...

Question 20

In which of the following do the mucous membranes serve as a portal of entry for disease?

Accepted Answer

Mucous membranes in the nasal cavity and eyes can serve as a portal of entry for disease when contaminated fingers or objects introduce pathogens into these areas.

Quiz 14: Infection, Infectious Diseases, and Epidemiology