NURSEDOCS Chapter 01 Copyright Macmillan Learning. Powered by Cognero. Page 1 1. Two of the main, early theories proposed to explain how antigen-specific antibodies develop were the instructional theory and the selective theory. How did the two differ? Which was ultimately shown to be CORRECT? ANSWER: The selective theory says that, when an antigen receptor binds with an antigen, the cell becomes activated (or the cell is selected to proliferate and secrete more copies of the receptor). The instructional theory says that the antigen receptor molds itself to the antigen. The selective theory was shown to be correct. 2. Often, serendipity plays a role in significant scientific discoveries. In your own words, explain how serendipity led Pasteur to discover a cholera vaccine. ANSWER: Pasteur developed the vaccine in chickens, which were in short supply. He challenged groups of chickens with cholera bacteria—some of which were previously exposed to an attenuated version of cholera bacteria. Only the previously exposed animals were protected from a new challenge, which led to the use of weakened pathogens as vaccines. 3. Despite its having been eradicated on a global scale, smallpox is presently considered a potential bioterrorism threat. Why? Use evidence to support your answer. ANSWER: After eradication was achieved, smallpox vaccination programs largely ended. As populations continued to grow over time, an ever-increasing percentage of the human population remains unvaccinated and thus, is still susceptible to the disease. 4. Prior to 1999, it was claimed that a thimerosal additive in vaccines was contributing to the rising incidence of autism. If the claims were true, what resultant trend might you expect to observe in the rate of autism once thimerosal was removed from vaccines? ANSWER: One would reasonably expect a decrease in the rate of autism. However, cases of autism continued to rise after thimerosal was removed from vaccines in 2001. 5. Given the discovery and development of effective antibiotics, make an argument for the continued use of vaccines against bacterial pathogens. Use evidence to support your answer. ANSWER: Antibiotics are used for treatment of disease, not typically for prevention. Antibiotic treatment is not foolproof (considering the rising incidence of antibiotic resistance). Vaccines are a preventative measure, and prevention is the gold standard for infectious disease control measures. 6. You have a friend unfamiliar with immunology, and he asks you the following question: "Why do I need the flu shot every year, but don't need an annual chickenpox vaccine?" As a student of immunology, how would you explain this discrepancy to your friend? Use evidence to support your answer. ANSWER: The virus that causes the flu changes every year - as a result, a new flu vaccine must be prepared each year based on a predication of the most common forms of the virus likely to be encountered. Vaccines are specific in the type of pathogen against which they protect, and protection against one type does not guarantee protection against pathogens that are closely-related. 7. Provide one benefit and one drawback of generating random recognition receptors during the development of B cells. ANSWER: A benefit is having the capacity to recognize and respond to diverse pathogens as they evolve. A drawback is that some recognition receptors could potentially recognize and target host antigens. (Kuby Immunology Covid-19 Digital Update, 8e Jenni Punt, Sharon Stranford, Patricia Jones, Judy Owen)
(Test Bank Latest Edition 2023-24, Grade A+, 100% Verified)
NURSEDOCS Name: Class: Date: Chapter 01 Copyright Macmillan Learning. Powered by Cognero. Page 2 8. A portion of our immune systems' white blood cells is constantly circulating throughout the body via circulation and lymphatics. What is the benefit of such circulation? ANSWER: The circulation of the white blood cells allows for a more comprehensive surveillance of the body for the presence of potential pathogens. A significant portion of the human body is constantly exposed to potential microbial pathogens. 9. Complete the following table by comparing and contrasting innate and adaptive immune responses. Innate Immunity Adaptive Immunity Is mediated by what cells? What do they recognize? How are the receptors encoded? Why can't they control all infections alone? What do they do in response to antigen? ANSWER: Innate Immunity Adaptive Immunity Is mediated by what cells? Macrophages, NK cells, neutrophils, mast cells eosinophils T cells and B cells What do they recognize? Pathogen patterns Specific epitopes How are the receptors encoded? Germ line Rearranged gene segments Why can't they control all infections alone? Pathogens evolve escape mechanisms Takes too long to develop What do they do in response to antigen? Engulf and destroy, induce inflammation Produce antibodies, kill infected cells 10. What are the hallmarks of inflammation? Describe the physical characteristics of someone experiencing an inflammatory response. ANSWER: Redness, swelling, heat, pain. Someone experiencing inflammation might have localized swelling and redness or itching or may be experiencing faintness due to a lowering of blood pressure if more severe. 11. Upon receiving immune serum as a treatment for a venomous snake bite, would the recipient be immune NURSEDOCS Name: Class: Date: Chapter 01 Copyright Macmillan Learning. Powered by Cognero. Page 3 from future bites of the same species? ANSWER: In the short -term, probably, as the serum contains protective antibodies against the venom. In the long-term, no, as serum treatment is a form of passive immunity. Passive immunity does not generate long-lived memory cells. 12. Provide one common feature of and two differences between B-cell receptors and PRRs. ANSWER: A common feature is that they both are used to recognize foreign antigens. A B-cell receptor is more selective than a PRR. The DNA that encodes for a PRR in an individual is inherited. The DNA that encodes for a mature B-cell receptor from an individual is not passed on to offspring. 13. Given that an important function of the immune system is to both recognize and dispose of cancerous cells, postulate why tumors can be established in a human host. ANSWER: There are two primary reasons. First, cancerous cells are self-originating, thus self-tolerance mechanisms can inhibit the development of an effective immune response. Second, as is common with some pathogens, genetic variability within a population of cancer cells gives them an advantage in terms of evading the immune response. 14. The hygiene hypothesis posits that there is a connection between environmental conditions and certain inappropriate immune responses. If you were a supporter of the hygiene hypothesis, what recommendations would you make to keep people healthier? ANSWER: Expose children to more common antigens found in dirt and in the outdoors. Reduce use of antimicrobials. 15. Which is the BEST definition of "immunity"? a. The state of having been exposed to a pathogen repeatedly b. The state of being resistant to reinfection with a pathogen c. When an individual has never been exposed to a pathogen d. When the immune system is activated e. When physical barriers are not enough to prevent infection ANSWER: b 16. What happens to a pathogen as it becomes attenuated? a. It becomes more dangerous to the host. b. It gets smaller. c. It has weakened virulence. d. It becomes older. e. All of the answers are correct. ANSWER: c 17. Which of the following advances can be credited to progress made in our understanding of immunology? a. Smallpox eradication b. Treatment of asthma c. Ability to transplant human organs NURSEDOCS
