Correct answer: (2) reducing the human population

Reducing the human population would do not harm to the lives of endangered species. It could be beneficial to them in so many ways. The major causes of the endangerment of species are habitat destruction, introduction of exotic species, and overexploitation. These factors are all effects of the increased human activity due to an increase in human population. For instance, wildlife habitats are disturbed when areas of land are developed into subdivisions or used to build factories. Or, humans bring exotic species to a new location where there could be few predators for those exotic species. Thus, the exotic species compete with the existing species-and since there are few predators, the exotic species replace the existing species that are in the same niche with the exotic species.

Incorrect answers:

(1) releasing more carbon dioxide into the atmosphere

Releasing more carbon dioxide in the atmosphere would cause greenhouse effect, and thus, climate change. This impacts the whole biosphere, most especially the endangered species.

(3) decreasing the amount of dissolved oxygen in the oceans

Decreasing the amount of dissolved oxygen in the oceans will harm the endangered species especially those that inhabit the ocean. Aquatic animals take in dissolved oxygen during respiration.

(4) reducing the thickness of the ozone layer

Correct answer: (3) recycling aluminum

Aluminum recycling is the process in which scrap aluminum is reused after its primary production. Aluminum is the most abundant metal in the earth's crust. However, a great amount of energy is required to extract it from ore. Thus, when aluminum is recycled, a lot of energy is saved, as well as the aluminum deposits in the crust.

Incorrect answers:

(1) deforestation

Deforestation is the removal of trees from the forest due to agricultural practices or urbanization. Although trees are considered as renewable resources, it takes years for trees to grow and replace those that are cut.

(2) removing carnivores from a forest

If carnivores are removed in the forest, there would be an ecological imbalance because they are important in the transfer of energy from one group of organism to another.

(4) heating homes with fossil fuels

• increased sediments
• pollution
• overfishing
• cutting down trees

• increased burning of fossil fuels
• more vehicles used
• increased in levels of deforestation
• increase in population

Option 3 – Development of equipment that uses solar energy to charge batteries

Sun light is the best natural resource that is converted into electricity. Rather than using expensive natural gas, oil, coal or wood for meeting energy requirements, you can save on a huge amount of money and electricity by utilizing the renewable solar energy.

Some of the environmental benefits resulting by the use of solar energy are

• •    Reduced air pollution
• •    Offset of greenhouse gases
• •    Reduced need for other sources of energy

Option 1 – decrease available habitats

Industrialization leads to increase in pollution, hence increasing global warming.

Industrialization is one of the parts in an ecosystem but, is not an element of stabilization.

Industrialization alone cannot lead to an increase in the carrying capacity of a native species in an ecosystem.

Carrying capacity refers to the number of individuals who can be supported in a given area within natural resource limits, and without degrading the natural social, cultural and economic environment for present and future generation

Initially, the water in the Rocky River is at 25 ^oC, and dissolved oxygen of 8.27 ppm. If they build a power plant which will release cold water (8 ^oC) into the river, the temperature will decrease. This also means that there will be an increase in the amount of dissolved oxygen, which is not the optimum amount for the survival of trout and black bass; and thus, might lead to a wiping out of these fishes' population in the Rocky River.

Correct Answer: (1) global warming

One of the major causes of global warming is the rising carbon dioxide concentration. Much of the solar radiation that strikes the planet is reflected back to the space. Even if carbon dioxide and water vapor in the atmosphere are transparent to visible light, they intercept and absorb much of the reflected infrared radiation, rereflecting it back to the Earth's surface.  This process keeps some of the solar heat.

Incorrect Answers:

Deforestation refers to the overharvesting of trees in the forest by means of logging or burning.

Mineral depletion is the decrease in amount of available minerals especially those from the soil.

Industrialization is a modernization process wherein technological innovation occurs in an previously agrarian community. There is a development of large-scale energy and metallurgy production.