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31. In general, a positive correlation exists between body size and generation time. This statement is: A) true; larger animals tend to have fewer offspring. B) false; the correlation is between small body size and longer generation time. C) false; however, a correlation exists between body size and type of survivorship curve. *D) true; larger animals tend to have a longer generation time. E) true; however, after reaching a certain body size, this correlation levels off.

*D) true; larger animals tend to have a longer generation time.

12. In logistic population growth, as the population size, N, approaches the environment's carrying capacity, K, what happens to the rate of population increase? A) It approaches zero. B) It decreases exponentially. C) It increases exponentially. D) It approaches K. E) It remains less than K.

A) It approaches zero.

22. Life history patterns: A) are subject to the pressures of natural selection. B) are usually learned. C) have no genetic component. D) exist only in organisms that exhibit parental care. E) show up in the fossils of plants.

A) are subject to the pressures of natural selection.

42. An inverted population pyramid represents _____, whereas a column-like population pyramid represents _____. A) declining growth; stationary growth B) increasing growth; declining growth C) stationary growth; increasing growth D) a young population; increasing growth E) increasing growth; stationary growth

A) declining growth; stationary growth

26. What life history trade-off characterizes big-bang reproducers, such as salmon? A) high parental investment and a large number of offspring B) an exceptionally high reproductive investment and early death C) production of a few large eggs and better survival of offspring D) delayed reproduction and great longevity E) delayed reproduction and significant growth

A) high parental investment and a large number of offspring

35. The death rate of organisms in a population exhibiting a type 3 survivorship curve is: A) lower after the organisms survive to the critical age of establishment. B) more or less constant throughout their lives. C) higher in post-reproductive than in pre-reproductive years. D) unrelated to age. E) usually correlated with density-independent causes.

A) lower after the organisms survive to the critical age of establishment.

32. A population's survivorship curve is a downward-sloping straight line when: A) the mortality rate is constant, regardless of age. B) juvenile mortality is extremely high. C) the mortality rate decreases with age. D) the birth rate exceeds the death rate. E) the mortality rate increases with age.

A) the mortality rate is constant, regardless of age

33. Organisms with a slow development and a high investment in their young will most likely have a __________ survivorship curve. A) type 1 B) type 2 C) type 3 D) type 1/type 2 hybrid E) type 2/type 3 hybrid

A) type 1

20. When a population reaches carrying capacity (K), it appears to persist indefinitely. One assumption could be that organisms stop dying. Which statement is a more likely explanation for this observation? A) The number of individuals arriving is exactly the same as the number of individuals leaving. B) As a population gets closer to the carrying capacity of its environment, its growth stops. C) The population is growing so quickly that it overshoots its carrying capacity. D) The rate of population growth is dependent on the resources available. E) More organisms are arriving into the population than leaving.

B) As a population gets closer to the carrying capacity of its environment, its growth stops.

47. Why is the carrying capacity for humans difficult to estimate? A) No one is certain about the size of the current world population. B) Humans have used technology to increase the carrying capacity for our population in a variety of ways. C) All nations currently have more available resources than are required to support their needs. D) Human populations never alter their fundamental growth properties. E) Carrying capacity is a concept that only applies to wild animals; it does not apply to human populations

B) Humans have used technology to increase the carrying capacity for our population in a variety of ways.

40. Field mice have few natural defenses. What other characteristics are also likely to be true about field mice? A) They age slowly. B) They reach sexual maturity early. C) They have long life spans. D) They live with low risk of predation. E) They have a low risk of death at each age.

B) They reach sexual maturity early.

25. Among mammals, litter size increases with distance from the equator. What is the likely reason for this trend? A) Mammals at higher latitudes exhibit more parental care toward offspring than mammals at the equator. B) To compensate for a shorter breeding season, mammals at higher latitudes produce more offspring per litter. C) Because it is often too hot to mate at the equator, mammals at higher latitudes have the advantage of being able to mate more often and also produce larger litters. D) More natural predators exist at higher latitudes; therefore, mammals living a greater distance from the equator produce more offspring to ensure survival. E) More competition for resources occurs at higher latitudes; therefore, mammals living at higher latitudes produce larger litters to outcompete other animals.

B) To compensate for a shorter breeding season, mammals at higher latitudes produce more offspring per litter.

3. The population size that a particular habitat can support indefinitely is called the: A) survivorship curve. B) carrying capacity. C) realized niche. D) fundamental niche. E) intrinsic population size.

B) carrying capacity.

9. Population density is determined by the number of: A) species in a given area. B) individuals of a species in a given area. C) individual organisms in a given area. D) breeding individuals of a species in a given area. E) interactions of populations in a community.

B) individuals of a species in a given area.

5. A population with an S-shaped growth curve is said to exhibit _____________ growth. A) density-dependent B) logistic C) biotic potential D) positive E) exponential

B) logistic

21. The point at which the maximum number of individuals are removed from a population without impairing its growth rate: A) is that population's carrying capacity. B) occurs when a population is halfway to its carrying capacity. C) is also when a population is growing at its slowest rate. D) is the definition of a density-dependent factor. E) is impossible to calculate.

B) occurs when a population is halfway to its carrying capacity.

1. When more than two members of the same species live in the same place at the same time, they constitute a(n): A) biome. B) population. C) community. D) niche. E) ecosystem.

B) population.

29. A life table: A) reflects the number of individuals in various age groups in a population at a given time. B) predicts survival and mortality rates for an individual at a given age. C) can be used to construct a population pyramid. D) shows the current birth and death rates of an entire population. E) predicts survivorship, but it cannot accurately predict mortality rat

B) predicts survival and mortality rates for an individual at a given age.

37. The physiological breakdowns that we experience as we age are the result of: A) natural selection selecting against alleles that cause death after sexual maturity. B) the cumulative effects of the buildup of late-acting mutant alleles in our genomes. C) not producing any offspring after maturity and, therefore, not passing along alleles for longevity. D) producing too many offspring after maturity, thereby "giving away" one's alleles for longevity. E) poor lifestyle choices, such as smoking or heavy drinking, early in life.

B) the cumulative effects of the buildup of late-acting mutant alleles in our genomes.

44. A primary difference in the age pyramids of industrialized versus third-world countries is that: A) mean longevity is significantly greater among third-world countries. B) third-world countries have much larger proportions of their population in the youngest age group. C) in third-world countries, the few who survive childhood live to a very old age. D) third-world countries show a characteristic "bulge" that indicates a baby boom. E) third-world countries have significantly more individuals than industrialized countries

B) third-world countries have much larger proportions of their population in the youngest age group.

41. Researchers have proven that life extension is possible. This statement is: A) true; scientists have successfully increased the longevity of human subjects in a laboratory setting. B) true; scientists were able to significantly increase the life expectancy of fruit flies in a laboratory setting. C) true; scientists have achieved this by selectively breeding fruit flies at the earliest possible age of maturity. D) false; scientists attempted to increase the life expectancy of fruit flies, but the average longevity was always 33 days. E) false; experiments to increase the longevity of living organisms have never been undertaken.

B) true; scientists were able to significantly increase the life expectancy of fruit flies in a laboratory setting.

17. The 20 adult females in a small population each have a probability of 0.5 of producing a single offspring each year and a probability of 0.5 of producing no offspring. How many female offspring will be produced each year? A) 50 offspring, because a female can produce twin and triplet births B) exactly 10 offspring per year C) 10 offspring per year on average, with some variation around this average D) exactly 20 offspring per year E) 20 offspring per year on average, with some variation around this average

C) 10 offspring per year on average, with some variation around this average

36. Which statement about natural selection is true? A) Natural selection operates only on people of advanced age. B) Natural selection has produced a high degree of infant mortality in humans, compared to other species. C) Natural selection "weeds out" alleles that cause death in early life. D) Natural selection has produced increasing numbers of people who choose never to have children. E) Natural selection tends to increase the risk of dying from external forces

C) Natural selection "weeds out" alleles that cause death in early life.

39. Which statement is true of giant tortoises? A) They evolved in environments with high mortality risk. B) They tend to reproduce early and often. C) They tend to age later and have long life spans. D) They evolved in environments with a high hazard factor. E) They have a high risk of death at any age.

C) They tend to age later and have long life spans.

28. A type 3 survivorship curve would be expected in a species in which: A) mortality occurs at a constant rate over the life span. B) parental care is extensive. C) a large number of offspring are produced, but parental care is minimal. D) mortality rate is quite low for the young. E) the life span is very short.

C) a large number of offspring are produced, but parental care is minimal.

30. Which choice best exemplifies an organism with a type 1 survivorship curve? A) oysters B) annual plants C) elephants D) sea turtles E) mackerel

C) elephants

45. Which phrase would characterize a pre-industrialized nation? A) low birth and death rates B) high levels of employment C) slow population growth D) reliable health care that is readily available E) efficient food production and distribution

C) slow population growth

19. In the oscillating cycle of growth seen in Canadian lynx and snowshoe hare populations, the hare population tends to grow when: A) lynx begin to reproduce at higher rates. B) lynx prey upon too many hares. C) the lynx population crashes. D) seasons change from fall to winter. E) seasons change from spring to summer

C) the lynx population crashes.

11. Populations that exhibit logistic growth still exhibit exponential growth. This statement is: A) false; populations exhibiting logistic growth show exponential growth when the population size is greater than the environment's carrying capacity. B) false; logistic growth occurs first, and as the population gets used to the food supply, exponential growth occurs. C) true; populations exhibiting logistic growth go through a period of exponential growth before growth rates level off around zero. D) true; logistic growth is another term for exponential growth. E) true; however, this can only occur in different populations of the same organism because one population cannot exhibit both types of growth.

C) true; populations exhibiting logistic growth go through a period of exponential growth before growth

4. When does the growth rate of a population equal zero? A) when N/K is one-half B) when N/K is zero *C) when deaths equal births D) when deaths exceed births E) when N is one

C) when deaths equal births

24. Which statement about life history patterns is generally false? A) The longer a species lives, the more offspring they are likely to leave behind. B) The greater the average size of offspring, the fewer offspring that are produced in a mating. C) The fewer the reproductive events, the longer individuals are likely to live. D) The greater the investment in reproduction, the longer a species is likely to live. E) Growth is slowed during periods when reproduction occurs.

D) The greater the investment in reproduction, the longer a species is likely to live.

8. In a population exhibiting logistic growth, what happens when the carrying capacity is exceeded? A) The population fluctuates around the new level. B) The carrying capacity cannot be exceeded, because population death precedes it. C) The population crashes and becomes extinct. D) The growth rate becomes negative until the population is back within the carrying capacity. E) The growth rate becomes zero until the population is back within the carrying capacity.

D) The growth rate becomes negative until the population is back within the carrying capacity

6. How does exponential growth differ from logistic growth? A) Logistic growth models take the population's age structure into account. B) Logistic growth requires a large population. C) Long-term exponential growth is more commonly observed than long-term logistic growth in nature. D) The logistic model of growth incorporates environmental limitations on population size. E) Exponential growth models include consideration of a population's carrying capacity

D) The logistic model of growth incorporates environmental limitations on population size.

43. From the following, select the best example of a cohort. A) a group of fish with the same mother and father B) a group of similarly banded butterflies C) a group of lizards from the same patch of desert D) a group of birds born in the same year E) a group of wolves that are capable of interbreeding

D) a group of birds born in the same year

38. An external force on a population that increases the risk of death is known as: A) aging. B) mortality. C) a density-independent factor. D) a hazard factor. E) a survivorship curve.

D) a hazard factor.

23. Which mammal would you expect to have the shortest gestation period? A) a giraffe B) a chimpanzee C) an elephant D) a mouse E) a human

D) a mouse

10. Natural populations fluctuate through time. One of the forces causing variation in population size is variation in the physical environment, which can have both direct and indirect effects on populations. Variation in population size linked to environmental factors (aside from those that occur daily or seasonally) is likely to: A) be predictable and constant. B) be density-dependent. C) affect the biotic potential exponentially. D) be irregular, perhaps even random. E) track the logistic growth model.

D) be irregular, perhaps even random.

14. At carrying capacity: A) a population's growth rate begins to decline. B) a population's death rate rapidly increases. C) purely abiotic factors prevent further population growth. D) population growth fluctuates around zero. E) birth rate becomes zero.

D) population growth fluctuates around zero.

27. A graph illustrating the proportion of individuals in a population that live to a given age is called a(n): A) logistic curve. B) growth curve. C) exponential growth curve. D) survivorship curve. E) death extrapolation

D) survivorship curve.

2. Define "ecology." A) the study of heredity and variation of inherited traits B) the study of plants C) the study of the physical history and structure of the earth D) the study of the interactions between organisms and their environments E) the study of living organisms and their parts

D) the study of the interactions between organisms and their environments

16. Exponential growth can continue indefinitely only if: A) the population starts out very small. B) the population starts out high but grows slowly. C) the carrying capacity of the habitat (K) is very high. D) the carrying capacity of the habitat (K) is a moderate figure. E) Exponential growth cannot continue indefinitely.

E) Exponential growth cannot continue indefinitely.

34. A survivorship curve that had low survivorship in the beginning and stabilized after high initial mortality would be a characteristic of which type of organism? A) rodents B) hummingbirds C) birds of prey D) elephants E) cod

E) cod

13. The growth rate of a population at its carrying capacity: A) depends on the carrying capacity of the population. B) is negative. C) is logistic. D) is at its maximum. E) fluctuates around zero.

E) fluctuates around zero.

18. Explosive population growth: A) is seen more often in nature than logistic growth patterns. B) is often followed by members of the population committing suicide. C) can continue unchecked, as long as food and shelter are available. D) can lead to a population exceeding its carrying capacity. E) is rarer in nature than logistic population growth

E) is rarer in nature than logistic population growth

15. In the equation for logistic growth, when N = K: A) population growth is doubles. B) population growth becomes bimodal. C) population growth rate is declining, though the population itself is still increasing. D) the population has exceeded carrying capacity. E) population growth stops.

E) population growth stops

7. Which choice is not an example of a density-dependent limiting factor that will influence carrying capacity? A) food supply B) predation C) disease D) territory availability E) water quality

E) water quality