The twentieth-century population explosion combined with a rapid escalation in human consumption, magnifies humanity’s impact on the Earth. Adjectives such as “calamitous’ and “catastrophic” are often used to describe this impact. 3. Why is Earth often called the Blue Planet? A. Because 70 percent of its surface discovered by water, and views from space are dominated by blue hues and swirls of white clouds. 4. Describe the Comet Hypothesis: A. Proposes that icy comets bombarded the Earth for more than a billion years, while its atmosphere was still thin, accumulating fresh water from space that filled the basins in the formative crust. . Define Pacific Ring of Fire: A. Ocean-girdling zone of crystal instability, volcanism, and earthquakes resulting from the tectonic activity along plate boundaries in the region. 6. When do scientists suggest that Homo sapiens appeared on the Earth? A. A warming phase that occurred between 120,000 and 100,000 years ago. 7. What came close to exterminating humanity about 73,500 years ago? A. Mount Toby erupted. This was not just an eruption: the entire mountain exploded, sending millions of tons of debris into orbit, obscuring the sun, creating long- term darkness, and altering global climate. 8.
What do some bio geographers suggest the next great extinction may be caused by? A. The next great extinction may be caused not by asteroids, but by humans, whose numbers and demands are destroying millions of species. 9. No species, not even the as strongly as ever affected their environment do today. A. Powerful dinosaurs, humans. 10. What ushered in the Black Death that swept over an already weakened Europe in waves that often killed half the population or more? A. As the Mongol migrants penetrated westward, their horse caravans picked up the strain of bacteria that brings on the bubonic plague, and its vector, the flea, rode into Europe. 1. Late in the fourteenth century, what legendary admiral authorized the construction of an ocean going fleet that would eventually number more than 6,000 ships, carrying as many as 500 people each? A. Admiral Chunk Ho 12. In North America, what colony collapsed so fast that the chief cause may well have been environmental? A. The Jamestown Colony 13. What event happened in April of 1815 on the island of Sumatra that killed all but 26 of the islands population of 12,000? A. The Tambala Volcano exploded in a series that could be heard thousands of miles away, covering the colony in darkness and poisonous ash for weeks. 4. How many types of organisms do Biologists estimate that there are on Earth? A. About 25 million types 15. Besides providing us with oxygen, what else does the atmosphere do for us? A. It shields us from the destructive rays of the sun; it moderates temperature; ND it carries moisture from the oceans over the land sustaining crops and forests, and replenishing soils and wells. 16. How is acid rain causing our environment to change? A. Acid rain is causing acidification of lakes and streams; stunted growth of forests; loss of crops in affected areas.
In cities, corrosion of buildings and monuments has accelerated. 17. Define Deforestation. A. Clearing and destruction of forests to harvest wood for consumption; clear land for agricultural uses; and make way for expanding settlement frontiers. 18. Why has soil erosion increased so much? A. As the pressure on land increases, farmers are less able to leave part of their soil unused to allow it to recover its nutrients. Shifting cultivators must shorten their field rotation cycle, and as a result their soil is less able to recover. 9. According to the textbook, what has grown faster than population? A. The waste generated by households, communities, and industries: Most of it is a matter of bulk. Some of it is a source of danger. 20. What is the purpose of a sanitary landfill? A. The role of a sanitary landfill is to store the waste of humans without vermin ululating; to not let methane gas into the air from decomposition; to keep rain and waste liquids from carrying contaminants into the ground water below; and to keep the waste from catching on fire. 1. What are the differences between toxic wastes and radioactive wastes? A. Toxic wastes release dangerous chemicals and infectious materials. Radioactive wastes release different levels of radiation. 22. What does the term biodiversity refer to? A. Biodiversity refers to the diversity of all aspects of life found on the Earth. It encompasses the entire range of biological diversity. 23. How many species are here? A. Estimates range from 10 million to 100 million, and no one is quite sure how many. So far only some 1. 5 million species have been identified. 24. Identifying the nature and extent of environmental changes is only the first step toward understanding the extent of human alteration of the planet. What is the second? A. The second, and more complicated step is to consider the forces driving these changes. 25. Because humans across the world don’t in exactly the same ways, we cannot make a simple chart saying that each additional human born on Earth results in a certain amount of A. Consume, pollute, consumption and pollution 26.
How does technology affect all aspects of our lives? A. We are continually developing technologies that we hope will improve our standard of living, protect us against disease, and allow us to work more efficiently. 27. Modes of transportation represent some of the most important technological advances in human history. How? A. Each innovation in transportation has required increased resource use. Not only to make the vehicles that move people and goods, but also build and maintain the related infrastructure, i. E. Dads, railroad tracks, airports, parking structures, repair facilities, and the like. 28. Why is the ozone layer so important? A. It protects the Earth’s surface from the Sun’s harmful ultraviolet rays. 29. What was the Montreal Protocol? A. The Montreal Protocol called for a 50% reduction in the production and consumption of CIFS by 1999. 30. What is one possible solution to the carbon dioxide emissions problem? A. The creation of a global carbon market, through which countries could exchange carbon dioxide emissions for preservation of carbon-absorbing forests.