Book cover for Biology

Biology

Sylvia S. Mader, Michael Windelspecht

ISBN #9780078024269

12th Edition

687 Questions

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153,501 Students Helped

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Summary
Learning Objectives
Key Concepts
Example Problems
Explanations
Common Mistakes

Summary

Chapter 46 provides a comprehensive overview of the major ecosystems of the biosphere by explaining how climatic factors, driven by solar radiation, Earth’s tilt, and rotation, shape both terrestrial and aquatic environments. It highlights the formation of atmospheric circulation cells, the dynamics of lake stratification and turnover, and the significant impact of human activities such as invasive species and biomagnification on ecosystem health. Key takeaways include the interconnectivity of climate processes with ecosystem characteristics and the importance of preserving biodiversity.

Learning Objectives

1

Explain how solar radiation, Earth’s tilt, and rotation influence global climate and the biosphere.

2

Describe the formation and role of atmospheric circulation cells in determining weather patterns and biomes.

3

Differentiate between the characteristics of terrestrial ecosystems (e.g., tundra, tropical rainforests) and aquatic ecosystems (e.g., lake stratification, ocean currents).

4

Analyze the impact of human activities on ecosystems, including biomagnification and invasive species.

Key Concepts

CONCEPT

DEFINITION

Solar Radiation

The energy emitted by the sun, which drives climate systems and weather patterns on Earth.

Earth's Tilt

The angle of Earth's axis relative to its orbital plane, influencing seasonal variations and distribution of sunlight.

Atmospheric Circulation Cells

Large-scale movement patterns of air that redistribute heat and moisture around the planet, helping to form climate zones and biomes.

Terrestrial Ecosystems

Land-based ecosystems, such as tundra, deserts, temperate forests, and tropical rainforests, each with distinct climatic and biological characteristics.

Aquatic Ecosystems

Water-based ecosystems, including lakes and oceans, characterized by processes like stratification, turnover, and the influence of currents.

Lake Stratification and Turnover

Stratification refers to the layering of water in lakes due to temperature differences, while turnover is the mixing process that occurs when these layers equalize seasonally.

Biomagnification

The process by which the concentration of toxins increases as they move up the food chain, impacting biodiversity.

Invasive Species

Non-native organisms that enter and disrupt existing ecosystems, often leading to reduced biodiversity.

Example Problems

Example 1

The seasons are best explained by a. the distribution of temperature and rainfall in biomes. b. the tilt of the Earth as it orbits about the sun. c. the daily rotation of the Earth on its axis. d. the fact that the equator is warm and the poles are cold

Example 2

Which region on Earth receives the largest amount of direct solar radiation throughout the year? a. Northern Hemisphere above 60° b. Northern Nemisphere between 30° and 60° c. Southern Nemisphere below 60° d. Southern Nemisphere between 30° and 60° e. the equator, between 30° north and 30° south

Example 3

Why are lush evergreen forests present in the Pacific Northwest of the United States? a. The rotation of the Earth causes this. b. Winds blow from the ocean, bringing moisture. c. They are located on the leeward side of a mountain range. d. Both b and c are correct. e. All of these are correct

Example 4

Which biome is associated with the rain shadow of a mountain? a. desert b. tropical rain forest c. taiga d. coniferous forest e. chaparral

Example 5

Which of these influences the location of a particular biome? a. latitude b. average annual rainfall c. average annual temperature d. altitude e. All of these are correct.
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Step-by-Step Explanations

QUESTION

How do atmospheric circulation cells form and influence climate zones?

STEP-BY-STEP ANSWER:

Step 1: Recognize that solar radiation heats the Earth unevenly because of its spherical shape, resulting in temperature gradients.
Step 2: Understand that Earth's tilt and rotation cause variations in solar heating, generating differential heating across latitudes.
Step 3: Identify that these temperature differences create pressure gradients, which drive the movement of air, forming circulation cells.
Step 4: Explain how these cells (e.g., Hadley, Ferrel, and Polar cells) redistribute heat and moisture, thereby establishing distinct climate zones and biomes.
Final Answer: Atmospheric circulation cells form due to uneven solar heating and pressure differences, and they play a crucial role in determining global climate patterns and biomes.

Atmospheric Circulation Cells

QUESTION

What is the process of lake stratification and subsequent turnover?

STEP-BY-STEP ANSWER:

Step 1: Clarify that during warm periods, the sun heats the surface layers of a lake, creating a temperature gradient (stratification) where the warmer water sits atop the cooler water.
Step 2: Note that temperature differences cause density differences, preventing mixing between the layers.
Step 3: Describe how during cooler periods (autumn or spring), the temperature of the upper layer decreases, evening out the water temperatures.
Step 4: Explain that once temperatures are uniform, the water layers mix in a process known as turnover, which redistributes oxygen and nutrients throughout the lake.
Final Answer: Lake stratification occurs when temperature differences create separate layers in a lake, and turnover happens when temperature equalization causes these layers to mix, ensuring nutrient distribution.

Lake Stratification and Turnover

QUESTION

How do human activities such as introducing invasive species and causing biomagnification affect ecosystems?

STEP-BY-STEP ANSWER:

Step 1: Define invasive species and understand that when non-native species are introduced, they can out-compete local species for resources.
Step 2: Discuss how changes brought by invasive species can alter ecosystem structure and function, leading to biodiversity loss.
Step 3: Define biomagnification and recognize that pollutants, once introduced into an ecosystem, become more concentrated as they move up the food chain.
Step 4: Explain the cumulative negative effects these processes have on both terrestrial and aquatic ecosystems.
Final Answer: Human activities such as introducing invasive species and causing pollutant biomagnification disrupt ecosystem balance, leading to reduced biodiversity and altered ecosystem processes.

Human Impacts on Ecosystems

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Common Mistakes

  • Assuming that solar radiation affects all regions of the Earth equally, ignoring the role of Earth's tilt and rotation.
  • Overlooking the importance of atmospheric circulation cells in creating distinct climate zones.
  • Confusing lake stratification with turnover, not recognizing them as sequential seasonal processes.
  • Underestimating the cumulative impact of human activities on both terrestrial and aquatic ecosystems.