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Chapter 3: SOIL: THE ORIGIN OF LIFE
Answers to Review Questions
TRUE/FALSE
1. Most plant life is dependent on the soil.
2. If there were no soil, there would be no plants for land animals to eat.
3. A process called the food chain begins with the soil.
4. Minerals have chemical and physical properties that can be formed into soil.
5. Organic soil is rich in nutrients.
6. The largest of the soil products is sand.
7. If the soil is too alkaline, acid materials are added to the soil.
8. The most common soil microorganisms are the bacteria.
9. Soil is made up only of minerals and decaying plant matter.
10. The roots of most plants cannot reach very far into the soil.
MULTIPLE CHOICE
1. A plant obtains nutrients from the soil and uses them through energy from
2. Humus is another word for
3. Soil that has been transported and deposited by moving water is called
4. Fine soil particles like silt and clay that have been deposited by the wind create
soil known as
5. In many of the mountainous regions of the world, soil was formed by the action of
6. Fertilizers provide plants with
7. Plants that host rhizobia are called
8. One-celled organisms that live in moist soil are called
9. Plantlike organisms that contain no chlorophyll are called
10. The area of the soil that contains the roots of plants is called the
DISCUSSION
1. Soil is composed of what materials?
2. Why is plant life dependent on soil?
3. How is soil classified?
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4. List two ways soil can be deposited.
5. What is loam soil?
6. What is the problem with too much clay in soil?
7. What are soil horizons?
8. What is the carbon cycle?
9. What is a symbiotic relationship?
10. What are the three basic groups of nematodes?