Human Impact Quiz

The dotted line on the graph below represents the potential size of a population based on its reproductive capacity. The solid line on this graph represents the actual size of the population. Which statement best explains why the actual population growth is less than the potential population growth?

• The final population size is greater than the carrying capacity.

• More organisms migrated into the population than out of the population.

• The birthrate gradually became greater than the death rate.

• Resources in the environment are limited.

The tall wetland plant, purple loosestrife, was brought from Europe to the United States in the early 1800s as a garden plant. The plant's growth is now so widespread across the United States that it is crowding out a number of native plants. This situation is an example of

• an unintended effect of adding a species to an ecosystem

• the results of the use of pesticides

• the recycling of nutrients

• the flow of energy present in all ecosystems

Scientists are concerned that the destruction of the ozone layer is allowing more ultraviolet radiation to reach the surface of the Earth. The chief reason for this concern is that ultraviolet radiation often acts as a

• mutagenic agent

• growth inhibitor

• pollutant

• biocide

The widest variety of genetic material that can be used by humans for future agricultural or medical research would most likely be found in

• areas that contain only one or two species

• a large field of a genetically engineered crop

• a forest that is planted and maintained by a forest service

• an ecosystem having significant biodiversity

Changes in the chemical composition of the atmosphere that may produce acid rain are most closely associated with

• runoff from acidic soils

• flocks of migrating birds

• industrial smoke stack emissions

• insects that excrete acids

Which practice will help conserve soil resources?

• planting cover crops on slopes along highways

• increasing the expansion of urban areas

• opening more forests to unregulated hunting

• filling in wetlands with construction waste

The rapid destruction of tropical rain forests may be harmful because

• the removal of trees will limit the construction of factories that will pollute the environment

• energy cycling in the environment will stop

• genetic material that may be useful for future medical discoveries will be lost

• removing trees will prevent scientists from studying ecological succession

Rabbits are not native to Australia. They were imported by European settlers. In 1936, the myxoma virus was introduced into Australia as a means of biological control to infect and reduce the rabbit population. This method of controlling the rabbit population was an attempt to

• stop the overproduction of an introduced species

• limit the food sources of the rabbit

• stop the overpopulation of a native species

• limit the number of rabbits brought into the country

Deforestation will most directly result in an immediate increase in

• atmospheric ozone

• wildlife populations

• atmospheric carbon dioxide

• renewable resources

Which relationship can correctly be inferred from the data presented in the graphs below?

• As oxygen content decreases, carp population decreases.

• As sewage waste increases, oxygen content increases.

• As sewage waste increases, oxygen content decreases.

• As oxygen content decreases, trout population increases.