Extensive data from hospitals have shown that infants born with intermediate weights
are the ones most likely to survive. This is a classic example of which type of selection?
a. directional selection
b. stabilizing selection
c. disruptive selection
d. natural selection
e. no selection
b
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The ultimate source of energy trapped during photosynthesis is
(a) CO2. (b) H2O. (c) O2. (d) sunlight.
A common adaptation of coastal plants that grow on sand dunes is
A. deep roots to extract moisture. B. broad leaves for enhanced photosynthesis. C. secretion of proteinaceous threads. D. increased transpiration of water. E. elevated growth rates.
At a research conference, you meet a graduate student who studies the hormonal underpinnings of mating behavior in two species of squirrel. "It turns out the difference between my two squirrel species is similar to the difference between the prairie and the montane voles," he says. You nod knowingly, and reply...
A. "Oh, so the promiscuous species has a lot of vasopressin and oxytocin receptors in the nucleus accumbus, blocking pair bonding, and the monogamous species doesn't?" B. "Oh, so the monogamous species has a lot of vasopressin and oxytocin receptors in the nucleus accumbus, promoting pair bonding, and the promiscuous species doesn't?" C. "Oh, so the polyandrous species has a lot of serotonin and dopamine receptors in the nucleus accumbus, promoting pair bonding, and the promiscuous species doesn't?" D. "Oh, so the monogamous species has a lot of serotonin and dopamine receptors in the nucleus accumbus, promoting pair bonding, and the promiscuous species doesn't?" Clarify question: What is the key concept addressed by the question? What type of thinking is required? Gather Content: What do you already know about the hormones involved in mating in the species of voles? What other information is related to the question? Choose Answer: Given what you now know, what information is most likely to produce the correct answer? Reflection on Process: Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
For a marine fish, the output from the kidney in Figure 48-2 would be:
a. a small volume of hypotonic urine. b. a large volume of hypotonic urine. c. a small volume of hypertonic urine. d. a large volume of hypertonic urine. e. a small volume of isotonic urine