1. Nucleic acid sequences that undergo few changes over the course of evolutionary time are said to be conserved. Conserved sequences of nucleic acids...
A. include all mitochondrial DNA
B. are abundent in ribosomes
C. comprise a larger proportion of pre-mRNA (immature mRNA) than of mature mRNA
D. are found in the most crucial portions of protiens
E. are proportionately more common in eukaryotic introns than in eukaryotic exons.
2. Prokaryotic ribosomes differ from those present in eukaryotic cytosol. Because of this, which of the following is correct?
A. Prokaryotes are able to use a much greater variety of molecules as food sources than can eukaryotes.
B. Translation can occure at the same time as transcription in eukaryotes but not in prokaryotes.
C. Some selective antibiotics can block protien synthesis of bacteria without effects on protien synthesis in the eukaryotic host.
D. Eukaryotes did not evolve from prokaryotes.
E. Some antibiotics can block the synthesis of peptidoglycan in the walls of bacteria.
3.If all fungi in an enviornment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?
A. mutualistic fungi
B. animals
C. plants
D. prokaryotes
E. protists
4. Which of the following statements describes the lysogenic cycle of lambda phage?
A. The phage DNA is incorporated by crossing over into any nonspecific site on the host cell's DNA
B. Certain enviornmental triggers can cause the phage to exit the host genome, switching from the lytic to the lysogenic.
C. The phage genome replicates along with the host genome.
D. After infection, the viral genes immediately turn the host cell into a lambda-producing factory, and the host cell then lyses.
E. Most of the prophage genes are activated by the product of a particular prophage gene.
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