Which of the following presents the greatest challenge to the development of a vaccine against HIV?
A. HIV doesn't provoke the production of antibodies.
B. Surface antigens on HIV change readily due to frequent mutations.
C. Individuals are unwilling to participate in vaccine trials out of fear of developing AIDS.
D. Antibodies against HIV don't provide any protection from infection.
Answer: B
You might also like to view...
Blood cultures are drawn on a patient suspected of having a fungemia. Positive cultures reveal the presence of chlamydoconidia on cornmeal agar. In addition, the yeast is germ tube positive. The most likely identification of the fungal agent is:
a. C. glabrata. b. C. tropicalis. c. C. neoformans. d. C. albicans.
The plant hormone ____ is primarily responsible for helping break the dormancy of seeds and buds
a. gibberellin b. cytokinin c. ethylene d. auxin e. jasmonate
Which of the following is NOT a characteristic
of type 2 diabetes?
a. pancreatic islet cells are destroyed b. onset of symptoms typically begins in middle age c. obesity is a big risk factor d. diet and exercise can help control it e. all of these are characteristics of type 2 diabetes
Which of the following statements regarding animals is false?
A) Animals that eat plants are called herbivores. B) Animals that eat meat are called carnivores. C) Animals that live in or on their food source and eat their way through it are called suspension feeders. D) Animals that extract food particles suspended in the surrounding water are called fluid feeders.