V. Values discussion
Answer the following questions, then discuss your answers with your classmates.
1. How do you define the biotic structure?
a. It is soil quality and climate.
b. It is the way the categories of organisms fit together, с It is the environment.
d. other
2. What are the major abiotic factors?
a. Rainfall, temperature and light.
b. Species and organisms of a given region. с Water, wind, chemical nutrients.
d. other
3. What is the key observation in any study of the abiotic side of ecology?
a. Plants may be grown in a series of chambers.
b. Plants grow increasingly well until they reach some maximum-
c. Different species thrive under different conditions.
d. other
4. What is called the range of tolerance?
a. Maximum growth.
b. A range of several degrees.
с The entire span that allows any growth at all. d. other
5. What is a fundamental biological principle?
a. The plants experience increasing stress until they cannot survive.
b. Every species (both plant and animal) has an optimal range and zones of stress.
с Every species (both plant and animal) has limits of tolerance
with respect to every abiotic factor, d. other
6. What cannot some plants tolerate?
a. Intense freezing.
b. Several weeks of freezing temperatures, с Any freezing temperatures.
d. other
7. What is called the limiting factor?
a. Any one factor being outside its optimal range.
b. The factor that is limiting the growth, с Any factor that affects the organism, d. other
8. What is known as the Law of Limiting Factors?
a. Many plants may grow under the same conditions.
b. Any factor affects the organism.
с Any one factor being outside its optimal range at any given time
will cause stress and limit the growth of an organism, d. other
9. Who and when first presented the Law of Limiting Factors?
a. JimBourgin 1840.
b. Nebel Wright in 1850.
с Justus von Liebig in 1840. d- other °- What do observations since Liebig's time show? a- His law has much broader application.
48
Unit Four
Ecosystems: What They Are
49
b.
It may be applied to biotic factors as well, с
His
law may be applied to all abiotic factors, d.
other
11. What does the biosphere consist of?
a. Plants, animals, and microbial species.
b. All abiotic factors.
с A great variety of environments, both aquatic and terrestrial, d. other
12. What is the spread of each species at some point limited by?
a. It's not being able to restrain its own spread and influence.
b. It's not being able to tolerate particular conditions, с It's not being able to compete with other species, d. other
13. What idea do many environmentalists promote?
a. Nothing can be changed without affecting everything else to a greater or lesser degree.
b. Most if not all life may perish.
с We may be on the verge of a sudden and catastrophic "collapse
of the biosphere", d. other
14. What do cornucopians argue?
a. Humans have already caused the extinction of thousands of species.
b. All our experience to date should lead to the quite opposite con clusion.
с Humans have already made manifold changes over most of the
earth, d. other