A scientist wants to study the effect of vitamin C on colds. He recruits 100 people with colds and gives the experimental group 1000 mg of vitamin C per day. What would be an appropriate control?
A. Give the control group orange juice every day.
B. Give the control group nothing.
C. Give the control group 1000 mg of another brand of vitamin C per day.
D. Give the control group 2000 mg of vitamin C per day.
E. Give the control group a pill similar to vitamin C but containing sugar (a placebo).
Answer: E
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What is a single-nucleotide polymorphism?
A. any point mutation B. the presence of single nucleotides in the DNA double helix C. a site where a restriction enzyme cuts D. a site where RNA polymerase binds to DNA E. None of the above is correct.
When Calvin injected 14C labeled CO2 into cultures of green algae, what led him to conclude that rubisco adds CO2 to ribulose bisphosphate in the Calvin cycle?
A. Radioactivity appeared last in ribulose bisphosphate. B. Radioactivity first appeared in glucose. C. Radioactivity first appeared in ribulose bisphosphate. D. Radioactivity appeared last in glucose. E. Radioactivity first appeared in 3-phosphoglycerate. F. Radioactivity appeared last in 3-phosphoglycerate
Four of the following were innovations that led to new adaptive zones. Select the exception
a. flight-capable wings in birds b. amniotic eggs in early reptiles c. Galápagos finches evolved to eat differently sized seeds d. sperm cells carried in pollen grains in seed plants e. silk glands in spiders
The situation in which an embryo produced as a
result of a mating between individuals of different species is incompatible with the mother and is subsequently aborted is an example of a. temporal isolation. b. hybrid inviability. c. mechanical isolation. d. gametic mortality. e. behavioral isolation.