Using a mouse model, the investigator orally inoculates mice with a mutated strain of Brucella lacking the gene for production of urease. Indicate which of the following would LEAST support the hypothesis that urease plays a role as a virulence factor in establishing Brucella infection.
a. Mice infected with mutated Brucella will NOT demonstrate inhibition of phagosome acidification by ammonia.
b. Mutant and nonmutant strains will demonstrate the ability to transition through intestinal mucosa.
c. Counts of viable mutant strains from the upper gastrointestinal (GI) tract will be significantly less than those of nonmutant strains.
d. Mice infected with nonmutated Brucella will demonstrate inhibition of phagosome acidification by ammonia.
Ans: b. Mutant and nonmutant strains will demonstrate the ability to transition through intestinal mucosa.
You might also like to view...
Which of the following statements about global warming is correct?
A. Higher latitudes have warmed more than equatorial regions. B. Overall, Earth's mean surface temperature has increased by only 0.5 degrees. C. A comparison of temperature data collected between 1999 and 2008 to temperature data collected between 1940 and 1980 shows that all environments on Earth have experienced an increase in mean annual temperature. D. Oceanic environments have warmed more than terrestrial environments. E. None of the answer options are correct.
The neurotransmitter, __________, is used by motor neurons to communicate with muscle cells.
A. acetylcholine B. GABA C. glutamine D. fatty acids E. serotonin
Each of the following is true about botulinum toxin (Botox) except
A) The toxin is one of the most potent toxins known. B) Botox is a SNARE protein. C) It can be used therapeutically to stop muscle spasms. D) It has been used to remove wrinkles caused by muscle contractions. E) It has potential use as a migraine headache treatment.
The head louse and body louse both are of the genus
a) Trichophyton. b) Candida. c) Sarcoptes. d) Pediculus.