Unit 13-Human Impact & Biodiversity

Which illustrates the human population's increased understanding and concern for ecological relationships?

• importing organisms in order to disrupt existing ecosystems
• allowing the air to be polluted only by those industries that promote technology
• removing natural resources from the Earth at a rate equal to or greater than the needs of an increasing population
• developing animal game laws in order to limit the number of organisms that may be killed each year

An example of a human activity that has had a positive effect on the environment is the

• disruption of natural habitats through urbanization
• exploitation of rare South American birds
• use of reforestation to control erosion
• uncontrolled hunting of endangered species of animals

The number of chemical industries along Georgia's rivers is steadily increasing. What is the most likely consequence of this increased industrialization?

• a decrease in the amount of water needed by industry
• a decrease in the amount of water pollution
• an increase in the destruction of natural food webs
• an increase in the amount of water available for recreational use

The creation of wildlife refuges and the enforcement of game laws are conservation measures that promote increased

• use of biocides
• preservation of species
• use of biological controls
• exploitation of species

American alligators used to be an endangered species, but they are not endangered anymore. Which of the following is the best reason why there are more American alligators in Louisiana today than there were 50 years ago?

• American alligators have learned to live in new places
• American alligators are bigger now than they were 50 years ago
• American alligators are now protected from hunting by humans
• American alligators have much more habitat than they did 50 years ago

In an effort to preserve wildlife on his farm, a farmer decides to stop using a 10-acre field. The farmer fences off the area, stops cutting the grass, and stops allowing livestock to graze there. After twenty years, the area would most likely

• be covered with moss and rocks
• be a mature hardwood forest
• be grown over with bushes and small trees
• be barren due to lack of maintenance

There is a limit to how large any given population can grow. Which of the following statements best explains why a population must eventually stop growing?

• A low female-to-male ratio develops in the population as it grows
• Old individuals outnumber juveniles in the population as it grows
• The resources available are fully used by the population as it grows
• Natural selection changes the gene pool of the population as it grows

When taken to a new habitat, non-native plants often threaten native plants of the new habitat. Why do non-native plants threaten native plants?

• Non-native plants are able to mutate rapidly
• Non-native plants cause native animals to relocate
• Non-native plants are able to be used for medicine
• Non-native plants compete with native plants for resources

An ecosystem contains organisms interacting with each other and their physical environment. Which of these is the best indicator of a healthy ecosystem?

• There are few decomposers
• There are many different species
• There are few herbivores
• There is a large population of only one species

The Georgia Department of Natural Resources is making an artificial reef off the Georgia coast. How will this most likely affect the fish population?

• The fish population will have more diseases
• The fish population will increase in numbers
• The fish population will become endangered
• The fish population will be unaffected by reefs