Exam 16: Host-Microbe Interactions

Select the correct sequence for proving Koch's postulates. 1) The microorganism must be recovered from the experimentally infected hosts. 2) The microorganism must be present in every case of the disease. 3) The same disease must be produced when a pure culture of the microorganism is introduced into susceptible hosts. 4) The microorganism must be grown in pure culture from diseased hosts.

The chemical nature of exotoxins is that of a

Is it a good strategy for a microbe to adhere to a receptor that plays a critical function for a host cell?

The symbiotic relationship wherein both partners benefit is termed

A young couple brings their 3-month old baby to the emergency department where you work as a triage nurse. The parents tell you that the baby had a runny nose, low grade fever, and mild cough two days earlier, which they assumed was a cold. However, the cough has become significantly worse and they are really worried about the gasping sound the child makes when breathing in after a coughing spell. The baby's cough is so bad that she has been vomiting and is refusing to feed. You are concerned that the baby has pertussis, commonly known as whooping cough. You give the parents some information while they are waiting for a physician to examine their child. -You are very concerned about your patient because you know that B. pertussis releases three toxins that play a role in disease progression. One of these, pertussis toxin (PT) is an A-B toxin that causes an increase in mucus production by cells in the respiratory tract. The parents ask you to explain what you mean by an A-B toxin. Which of the following would you NOT tell them?

What is the difference between a primary pathogen and an opportunistic pathogen?

Newborn babies acquire microbiota

C5a peptidase

In two of Koch's postulates (#2 and #3), a pure culture of the organism is required. Which of the following would NOT be a possible consequence of using a contaminated culture?

Select the INCORRECT definition regarding the progression of an infectious disease.

The interaction of all organisms within a biological community with their environment is called a(n)

A young couple brings their 3-month old baby to the emergency department where you work as a triage nurse. The parents tell you that the baby had a runny nose, low grade fever, and mild cough two days earlier, which they assumed was a cold. However, the cough has become significantly worse and they are really worried about the gasping sound the child makes when breathing in after a coughing spell. The baby's cough is so bad that she has been vomiting and is refusing to feed. You are concerned that the baby has pertussis, commonly known as whooping cough. You give the parents some information while they are waiting for a physician to examine their child. -Pertussis is caused by Bordetella pertussis, an encapsulated, aerobic Gram-negative bacterium. You tell Baby A's parents that when Bordetella is inhaled, it attaches specifically to ciliated respiratory epithelial cells. Attachment is facilitated by ________ on the bacterium that attach to specific ________ on the host cells.

The normal microbiota provides protection against potentially harmful organisms and stimulates the immune system. Why would the immune responses to members of the normal microbiota cross-react with pathogens?

Species of both Shigella and Streptococcus

Which of the following is/are True about endotoxins?

Which of the following does S. pneumoniae use to survive in the host?

If a disease affects only a human and not an animal, then it would be difficult to fulfill Koch's postulate number ________.

A young couple brings their 3-month old baby to the emergency department where you work as a triage nurse. The parents tell you that the baby had a runny nose, low grade fever, and mild cough two days earlier, which they assumed was a cold. However, the cough has become significantly worse and they are really worried about the gasping sound the child makes when breathing in after a coughing spell. The baby's cough is so bad that she has been vomiting and is refusing to feed. You are concerned that the baby has pertussis, commonly known as whooping cough. You give the parents some information while they are waiting for a physician to examine their child. -The parents tell you that their baby has already had a DTaP vaccine and that they thought this would protect the child from pertussis. You explain that this vaccine is given in a series and that with each shot in the series, the child's immunity will increase. You explain that while their baby was born with ________ immunity, she only started to develop ________ immunity after birth, so is still vulnerable to certain infections such as pertussis.

You describe to Jay the initial events that must have occurred in order for him to become ill. Which of the following statements is False? 

The number of organisms necessary to cause infection is termed the