USABO Practice Exam Questions And Answers

USABO Practice Exam Questions And Answers What enzyme does HIV use to convert RNA to DNA? - ANS Reverse Transcriptase The promoter region of a prokaryotic gene is located ______ to the gene and is the binding site for ______. - ANS 5'...RNA polymerase Which of the following is TRUE of prokaryotes? I. Simultaneous transcription and translation II. Presence of intron sequences III. Circular DNA - ANS I and III only Integral transmembrane proteins are proteins imbedded in the cell membrane. Which of the following amino acids would you MOST expect to find in the transmembrane region of such proteins? - ANS Tryptophan When the base composition of DNA from bacterium Mycobacterium tuberculosis was determined, 18% of the bases were found to be adenine. What is the G + C content in M. tuberculosis? - ANS 64% The frequency of individuals affected with an autosomally recessive inherited disorder is 1 in 4. Assuming that the population affected by this disease is in Hardy-Weinberg equilibrium, what is the proportion of carrier individuals in this population? - ANS 50% The velocity of action potential conduction across a nerve axon is increased by the presence of the myelin sheath. In the peripheral nervous system, what cell myelinates the axon? - ANS schwann cell