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Read the statement below carefully. Answer True if you think…

Read the statement below carefully. Answer True if you think a statement it TRUE. Answer False if you think the statement is FALSE. Give a brief explanation or example to justify your answer. This strategy of biological control uses predators, pathogens, and parasitoids of crop pests rather than chemicals to control pest densities.

Read the following scenario and answer the question below. …

Read the following scenario and answer the question below.  Despite the high cost of the technology to design genetically modified (GM) crops, American companies have invested in their development. The first genetically engineered crop was the Flavr Savr tomato, which was created by reversing the function of a normal tomato gene. It was approved by the FDA for sale in the United States in 1994. Its grower, the Calgene Corporation, maintained that it would ripen longer on the vine, taste and ship better, and last longer on supermarket shelves compared to conventional tomatoes. It is no longer marketed because of technical problems and public safety concerns. Today, most engineered crops are modified for insect and herbicide resistance. In 1997, Monsanto Company first marketed GM corn. This Bt corn was engineered using genes from the Bacillus thuringiensis bacteria that made the corn resistant to some pests. In 1999, environmentalists were alarmed when it was reported that pollen from Bt corn could kill monarch butterfly larvae if corn pollen drifted onto milkweed plants that monarchs fed upon. Consumers feared the unknown and were concerned about potential food allergies. Presently, corn, along with soybeans, cotton, and canola dominate the GM food market. These crops are grown and distributed mostly in the United States, Argentina, Canada, Brazil, and China. They are used mostly for animal feed, clothing, or to make oil or other ingredients for processed food, which has helped them gain public acceptance. Although GM crops such as strawberries, potatoes, and lettuce have all been marketed in the United States, GM food field trials involving biotech fruits and vegetables have dropped significantly during the past several years, and the pace of new product introductions has fallen sharply. This narrow range of crops could mean that biotechnology may not realize its full potential in the future. The Flavr Savr tomato is no longer marketed because ________.

Read the following scenario and answer the question below. …

Read the following scenario and answer the question below.  Many geologists have proposed naming the current time period of Earth’s history the Anthropocene epoch. The rationale for doing so includes the fact that erosion rates and greenhouse gas levels in the atmosphere have increased rapidly over the past 300 years. Almost all environmental scientists agree that increases in greenhouse gases contribute to global climate change. Carbon dioxide, methane, nitrous oxide, hydrochlorofluorocarbons, and water vapor are the main culprits. Human activities, chief among them the extraction and burning of fossil fuels for energy, have significantly increased these “greenhouse gases” in our atmosphere in the last 300 years. With rising standards of living in developing countries, emissions of carbon dioxide and other greenhouse gases are expected to continue to rise. If unchecked, carbon dioxide levels will reach twice preindustrial levels by midcentury and double again by the end of the century. Computer models have shown that this rise alone could raise Earth’s temperatures by 3 to 10 degrees Fahrenheit by 2100. Preindustrial levels of atmospheric carbon dioxide have been estimated to be approximately 275 ppm (parts per million). If unchecked, carbon dioxide levels are expected to reach ________ ppm by the year 2100.