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Which statement best describes what is most likely to occur if an animal population grows larger than the carrying capacity of its environment?*
The graph below shows the size of a population of foxes over a period of years.
If the line did not stay around the carrying capacity, but continued to rise, which concept would this graph best illustrate?*
A scientist was studying a population of fish in a pond over a period of 10 years. He observed that the population increased each year for 3 years, and then remained nearly constant for the rest of the study. The best explanation for this observation is that the population had*
Base your answers to questions 4 on the data table below, which shows the estimated population of wolves in Minnesota from 1995 through 2002.
Directions: Using the information in the data table, construct a line graph on the grid, following the directions below.
The most likely explanation for the size of the wolf population for the 2000–2002 period is that the population*
A finite resource in the environment that keeps a population from steadily increasing is known as*
Which statement best describes how a major change in the size of one population affects an ecosystem?*
The Mississippi River Delta wetlands ecosystem is home to a large number of fish, birds, and other aquatic organisms. During the last century, this ecosystem has seen a decrease in wetland areas and species diversity due to land development, agriculture, and flooding. Conservation groups have been working to reconnect the Mississippi River with its flood plain and restore lost wetlands. One result of restoring wetland areas in this ecosystem would be*
The number of white-tailed deer in certain areas of Long Island, NY has increased significantly. Homeowners and farmers have put up tall fencing to protect their gardens and crops from the deer. One reason why the white tailed-deer might have increased significantly in certain areas of Long Island is*
Many bacteria and fungi are important in the environment because they*
Base your answers to questions 10 on the graph below and on your knowledge of biology. The graph shows interactions of moose and wolf populations on Isle Royale.
State one possible reason for the change in the moose population between 1995 and 1997. *
Base your answers to questions 11 on the information below and on your knowledge of biology.
Types of Predators
When large predators, such as lions or wolves, are removed from a food web, smaller “mesopredators” step in to take their places, and the results may be severe. Mesopredators are usually smaller and more numerous than the larger “apex” predators that they replace. Some are also omnivores, eating plant and animal food sources, rather than eating the meat-only diet of the largest predators. Examples of mesopredators include coyotes, raccoons, and skunks.
In 1874, General George Custer noted that there was an abundance of wolves, but few coyotes, in South Dakota. Today, there is an abundance of coyotes, but no wolves. The wolves were removed to protect domestic sheep, but now the coyotes are often responsible for attacking sheep and other animals. The cost of controlling mesopredators by human intervention can be very high, as mesopredators are very numerous and quickly “bounce back” after control efforts. Meanwhile, the number of apex predators that are endangered continues to increase.
Describe how the wolf population is controlled naturally in the environment without human intervention. *
Base your answers to questions 12 on the chart below and on your knowledge of biology. The chart shows seasonal changes in an ecosystem and the overall carrying capacity of the ecosystem.
Explain what is meant by the carrying capacity of a particular population in an ecosystem. *
Base your answers to questions 13 on the information and graph below and on your knowledge of biology. The graph contains information about an ecosystem.
The graph below shows the carrying capacities of an ecosystem for three different species, 1, 2, and 3, that inhabit an area and the actual population sizes of these three different species in the area.
Identify which species population would most likely have the greatest competition among its members. Support your answer using information from the graph. 
Base your answers to questions 14 on the graph below and on your knowledge of biology. The graph shows the size of a population over time.
State one reason for the changes in population size represented by line A between years 5 and 10. *
Base your answers to questions 15 on the passage below and on your knowledge of biology.
Ocean-dwelling (marine) iguanas and land iguanas inhabit the Galapagos Islands. Some scientists believe that both types of iguanas diverged from a common ancestor. Marine iguanas eat algae. Land iguanas feed on cacti. Algae are more abundant in the ocean than cacti are on the islands. Both species lay their eggs in the sand.
Rats, cats, and goats have been introduced to the islands by humans. Rats feed on iguana eggs, cats eat baby iguanas, and goats eat cacti.
Which population of iguanas, marine or land, would you expect to be larger? Support your answer. 
Population of iguana:*