A dental student wants to test if fluoride is an effective additive against tooth decay. The student studies tooth decay in a population of people who live in neighborhoods supplied with fluoridated water. This student would like to ask whether access to fluoridated water prevents tooth decay. What would be an effective control group to ask this question?
A. individuals who have fluoride added to their toothpaste but not their water
B. individuals with access to fluoridated water
C. individuals with access to differing amounts of fluoride in the water
D. individuals with access to water with no fluoride added
Answer: D
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In prokaryotes, the 30S pre-rRNA transcript is cleaved into:
A. two rRNAs. B. three RNAs. C. two rRNAs and tRNA. D. three RNAs and tRNA. E. multiple copies of three specific RNAs plus tRNA.
Methods for determining the linkage group and genetic map in humans involve ________
A) DNA markers B) zygotene and pachytene DNA synthesis C) twin spots and tetrad analysis D) chiasmatype and classical analyses E) tetrad analysis and bromodeoxyuridine
Which phrase best describes the characteristics of plasmodium?
A. Plasmodial slime molds are multicellular. B. Plasmodial slime molds consist of large multinucleate single cells. C. Plasmodium cells contain a pellicle. D. Plasmodial slime molds consist of large single nucleate cells.
A(n) ________ group is treated like an experimental group, except for the one variable being tested
Fill in the blank(s) with correct word