Populations grow exponentially

1. Populations grow exponentially 4.1 • when populations are relatively small and resources are plentiful. • when most mature individuals in the population have an opportunity to reproduce. • for an indefinite period of time, independently of resources. • when they follow an S-shaped growth curve. • under conditions described by 1 and 2.

2. Populations grow exponentially 4.1 • when populations are relatively small and resources are plentiful. • when most mature individuals in the population have an opportunity to reproduce. • for an indefinite period of time, independently of resources. • when they follow an S-shaped growth curve. • under conditions described by 1 and 2.

3. When a population reaches equilibrium, 4.2 • there are no new individuals born into the population. • the population will not change as long as the individuals live for a long time. • the number of individuals born into the population approximately equals the number of individuals dying. • the number of individuals can easily increase at any time. • every individual will have unlimited access to resources.

4. When a population reaches equilibrium, 4.2 • there are no new individuals born into the population. • the population will not change as long as the individuals live for a long time. • the number of individuals born into the population approximately equals the number of individuals dying. • the number of individuals can easily increase at any time. • every individual will have unlimited access to resources.

5. The reproductive strategy shown by most insect species is 4.3 • produce very many young, then provide them with attentive parental care. • produce relatively few young, but provide them with attentive parental care. • produce very many young, but allow them to take their chances without much parental care. • an example of low biotic potential. • so different from one species to another that it is impossible to make a generalization. DRMercer©

6. The reproductive strategy shown by most insect species is 4.3 • produce very many young, then provide them with attentive parental care. • produce relatively few young, but provide them with attentive parental care. • produce very many young, but allow them to take their chances without much parental care. • an example of low biotic potential. • so different from one species to another that it is impossible to make a generalization. DRMercer©

7. Environmental resistance is described by all of the following EXCEPT 4.4 • it is essentially zero when populations are very small. • it is relatively constant regardless of the population size. • it is the combination of natural factors that slows down the rate of growth for natural populations. • it is responsible for maintaining populations near their maximum sustainable equilibrium number. • it becomes greatest as populations approach their carrying capacities.

8. Environmental resistance is described by all of the following EXCEPT 4.4 • it is essentially zero when populations are very small. • it is relatively constant regardless of the population size. • it is the combination of natural factors that slows down the rate of growth for natural populations. • it is responsible for maintaining populations near their maximum sustainable equilibrium number. • it becomes greatest as populations approach their carrying capacities.

9. Which of the following mortality factors is density independent? 4.5 • transmission of infectious disease • lack of essential resources • late spring freeze in temperate region • infection by parasites • predation

10. Which of the following mortality factors is density independent? 4.5 • transmission of infectious disease • lack of essential resources • late spring freeze in temperate region • infection by parasites • predation

11. Which of the following is NOT true about the predator–prey relationships shown in Figure 4–5? 4.6 • Wolves can outnumber moose. • Peaks in the number of wolves occur sometime after peaks in the number of moose. • Wolves must be much less numerous than moose. • When wolf numbers are lowest, the moose population can begin to recover. • If both predator and prey are present, neither population will become so common that its environment is damaged.

12. Which of the following is NOT true about the predator–prey relationships shown in Figure 4–5? 4.6 • Wolves can outnumber moose. • Peaks in the number of wolves occur sometime after peaks in the number of moose. • Wolves must be much less numerous than moose. • When wolf numbers are lowest, the moose population can begin to recover. • If both predator and prey are present, neither population will become so common that its environment is damaged.

13. A keystone species 4.7 • is one that occupies the base level of a feeding pyramid. • is the most common species in an ecosystem. • is the largest species in an ecosystem. • is one whose removal would upset the relative populations of many other species within an ecosystem. • is a type of animal from Pennsylvania, known as the keystone state.

14. A keystone species 4.7 • is one that occupies the base level of a feeding pyramid. • is the most common species in an ecosystem. • is the largest species in an ecosystem. • is one whose removal would upset the relative populations of many other species within an ecosystem. • is a type of animal from Pennsylvania, known as the keystone state.

15. Competition 4.8 • can occur between individuals of the same species or individuals of different species that require a limiting resource. • happens only in mobile animals. • is generally resolved by violent conflict. • has impacts upon the performance of individuals in a population but little to do with the makeup of an ecosystem. • occurs because different species have the same abilities to exploit their environments.

16. Competition 4.8 • can occur between individuals of the same species or individuals of different species that require a limiting resource. • happens only in mobile animals. • is generally resolved by violent conflict. • has impacts upon the performance of individuals in a population but little to do with the makeup of an ecosystem. • occurs because different species have the same abilities to exploit their environments.

17. Invasive species generally cause problems because they 4.9 • have new biotic potentials within their new habitats. • are often introduced without appropriate environmental resistance factors. • occupy new trophic levels in their new habitats. • are unlike any organisms that previously occupied the invaded region. • are much larger than competing organisms within their new habitats.

18. Invasive species generally cause problems because they 4.9 • have new biotic potentials within their new habitats. • are often introduced without appropriate environmental resistance factors. • occupy new trophic levels in their new habitats. • are unlike any organisms that previously occupied the invaded region. • are much larger than competing organisms within their new habitats.

19. Adaptation results from 4.10 • a population improving itself. • individuals with traits that are better suited for environmental conditions producing more offspring than their competitors within a population. • individuals within a population changing their traits to better fit their surroundings. • the dying off of less fit individuals within a population. • constant expression of genetic traits within a population.

20. Adaptation results from 4.10 • a population improving itself. • individuals with traits that are better suited for environmental conditions producing more offspring than their competitors within a population. • individuals within a population changing their traits to better fit their surroundings. • the dying off of less fit individuals within a population. • constant expression of genetic traits within a population.