The great size and mobility of the vertebrates are likely the result of
A) uterine development of offspring.
B) increased brain size and complexity.
C) lungs used for respiration.
D) four-chambered hearts.
E) lightweight endoskeletons.
E
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Which of the following chemical differences contribute to increased structural variety of RNA over DNA?
A. In addition to the double-stranded regions, virtually all of the unpaired bases are involved in base stacking interactions, increasing the variety and stability of RNA. B. Since RNA molecules have no pucker the sugar molecules are flat and can add to stacking stabilization. C. Base stacking contributes less to RNA stability because fewerbases are paired. D. Because ribose has one less hydroxyl group there are fewer opportunities for RNA to hydrogen bond. E. Different sugar puckers cause the phosphates in the RNA backbone to be farther apart.
The biological species concept developed by
Ernst Mayr contains which of the following?
a. individuals that can potentially interbreed b. individuals that produce fertile offspring c. individuals that do not interbreed with other groups d. all of these except e. e. none of these
Hybridization between populations upon secondary contact may result in ________
A) reinforcement of the two original species by way of pre- or post-zygotic isolating mechanisms B) the creation of one or more new species as hybrids between the two parental species C) the creation of a hybrid lineage that has higher fitness than either of the parental species D) All of the above are possible. E) None of the above are possible.
Pseudogenes tend to have lower average substitution rates than functional genes
Indicate whether the statement is true or false