Which one of the following is likely to be associated with a loss of genetic diversity in a local population of a species?
A. The arrival of individuals of the same species from distant populations.
B. Genetic mutations.
C. A 90% reduction in the size of the population.
D. Mating with individuals from other populations.
Answer: C
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Geographers often use this type of density to compare conditions in different countries
A) physiological B) scientific C) arithmetic D) agricultural E) hypothetical
A secondary rainbow
A) is always brighter than a primary rainbow. B) produces a color pattern that is the same as a primary rainbow. C) is more likely when the Sun is straight over head, or nearly so. D) requires that light be reflected twice within a raindrop. E) all of the above
You are studying with a classmate, who explains that increasing the amount of nutrients in a lake helps submerged, rooted aquatic plants by providing them with the nitrogen and phosphorus they need to survive and reproduce. Which of the following should
be your response to your study buddy? A) You agree and point out that the resulting fish kill would further enhance the nitrogen and phosphorus levels in the lake, which would further enhance the growth of submerged aquatic plants, creating a positive feedback loop. B) You disagree and explain that plants cannot use the nutrients in the water because the plants do not have access to the nutrients. C) You agree because all organisms need nitrogen and phosphorus, and waterways are naturally limited in those nutrients. D) You agree and point out that plants also benefit because the decrease in oxygen will kill aquatic fish and snails, some of which would otherwise eat the aquatic plants. E) You disagree because the resulting increase in phytoplankton at the surface would inhibit sunlight from penetrating into the water, thus inhibiting photosynthesis in the submerged plants.
Drainage density refers to
A) the thickness of the water in the stream. B) the number of channels in an area. C) a measure determined by dividing the length of all the the channels by the area of its drainage basin. D) the arrangement of channels in a given area.