Contrary to popular belief, stress is not usually the primary cause of ulcers, and many patients with ulcers do not over-produce acid. What Nobel prize-winning discovery demonstrated a previously unknown cause of ulcers?
A. greater acid concentrations in the stomach, lower esophagus, and duodenum
B. the eroding effect of certain spicy foods on the lining of the esophagus
C. the existence of a bacterial infection in the stomachs of most patients with ulcers
D. genetically predetermined weakness in the walls of the intestinal tract
C. the existence of a bacterial infection in the stomachs of most patients with ulcers
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Dependence on animal for fertilization and dispersal is characteristic of many species of:
a. ferns b. angiosperms c. mosses d. conifers e. cycads
Dr. Jane Doe is investigating how robins navigate during their yearly migration. Which of the following would NOT be a component of a scientific inquiry into this question?
A. Ignoring/discarding results that disagree with her favored hypothesis. B. Proposing one or more potential mechanisms of navigation. C. Exploring the current scientific literature on avian migration. D. Designing an experiment to test one of her proposed mechanisms.
In a large population of randomly breeding organisms, the frequency of a recessive allele is initially 0.3. There is no migration and no selection. Humans enter this ecosystem and selectively hunt individuals showing the dominant trait. When the gene frequency is reexamined at the end of the year, __________.
a. The frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go up b. The frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will go up, and the frequency of the homozygous recessives will remain the same c. The frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will remain the same, and the frequency of the homozygous recessives will go up d. The frequency of the homozygous dominants will go up, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go down e. The frequency of the homozygous dominants will go up, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go up
According to an attorney cited by Schick, so-called "quack medicine" or "quackery" is relatively harmless
Indicate whether the statement is true or false.