science quiz

mkjaber

Main

Home >Homework Answsers >Science homework help

Ecological succession is halted to keep the agroecosystem in an early-successional state.

       The focus is on monoculture (one plant species instead of many).

       Crops are planted in rows and fields.

       Agroecosystems require plowing, which is unlike any natural soil disturbance.

       All of the above are valid ways that agroecosystems differ from natural ecosystems.

Question 2.2. Table 11.1 on page 215 of your text, Environmental Science, provides data regarding land, population, and agriculture. Based on the statistics provided in this table, which continent or continents use over 50% of their total land for agriculture? (Points : 1)

       Asia

       Europe

       Australia

       Both a & c

       All of the above (a, b, & c)

Question 3.3. Livestock are often raised on rangeland or pasture. What is/are the major difference(s) in rangeland and pasture? (Points : 1)

       Rangeland is not marked by fencing while pasture is surrounded with barbed or electric wire.

       Rangeland provides food for grazing without planting or plowing while pasture is plowed, planted, and harvested to provide forage for animals.

       Pasture does not utilize irrigation while rangeland is irrigated regularly.

       Pasture and rangeland are the same; however, the term pasture is utilized in the U.S. while rangeland is utilized in Europe and other parts of the world.

       All of the above

Question 4.4. While naturally occurring, organic fertilizers (fertilizers made of natural products such as manure) have a number of drawbacks to manmade artificial fertilizers, which of the following is a major drawback of organic fertilizers? (Points : 1)

       Organic fertilizers do not provide enough chemical elements to replace those lost during farming

       Organic fertilizers must be used in conjunction with regular irrigation to ensure effectiveness

       Organic fertilizers are toxic to animals which means they can’t be used on pastures

       Organic fertilizers are toxic to humans which means that they can’t be used on food crops

       None of the above

Question 5.5. Crops require about 20 separate chemical elements to survive. Liebig’s law of the minimum states that the growth of a plant is affected by just one limiting factor at a time – the nutrient whose availability is the most limited to the needs of a plant. Based on this law, which of the following statements is true? (Points : 1)

       Increasing the limiting nutrient will improve soil production

       Increased plowing will release nutrients and increase crop production

       Irrigation will stimulate carbon turnover and increase crop production

       Fertilization with a mixture including all of the soil micronutrients is necessary to improve crop growth

       None of the above

Question 6.6. Pest management strategies that utilize chemicals (pesticides) often lead to environmental damage, such as the contamination of drinking water. Which pest management technique(s) allow(s) farmers to control pests without applying harmful chemicals? (Points : 1)

       Application of broad spectrum inorganic toxins

       Application of artificial organic compounds

       Utilization of integrated pest management

       Use of biological controls

       None of the above

Question 7.7. Some people argue that eating lower on the food chain (eating plants instead of meat) is a more environmentally sustainable practice. Which statement or statements below accurately detail(s) the benefit(s) of eating lower on the food chain addressed in the textbook? (Points : 1)

       Eating lower on the food chain ensures that pesticide intake by the consumer is reduced.

       Eating lower on the food chain ensures sustainability of cattle populations.

       Due to organismal energy efficiency, eating lower on the food chain may allow the same area of farmland to produce between 10 and 100 times more vegetation per year than eating meat.

       Both a & b

       All of the above (a, b, & c)

Question 8.8. Genetic engineering in agriculture involves a number of different technical practices. Which following practice or practices mentioned in your textbook is/are considered current genetic engineering technologies? (Points : 1)

       Faster and more efficient development of new hybrids

       Introduction of the “terminator” gene

       Transfer of genetic properties from widely divergent kinds of life

       Both a & b

       All of the above (a, b, & c)

Question 9.9. The terminator gene makes seeds from a crop sterile. What is/are the reason(s) for inserting a terminator gene into a crop? (Points : 1)

       It prevents farmers from using the next generation of seeds so that they must purchase new seeds each year

       It prevents a genetically modified crop from spreading to nearby farms and natural areas

       It keeps Arnold Schwarzenegger away

       Both a & b

       None of the above

Question 10.10. Aquaculture (the farming of fish) provides many benefits to traditional fishing and/or farming practices. However, as with all sources of food production, it also has its drawbacks. Which of the following negative environmental impact or impacts discussed in your book is/are commonly caused by aquaculture? (Points : 1)

       Air pollution

       Damage of biological diversity

       Soil erosion

       Both a & c

       All of the above