Ch 5: Internal & External Environments

About This Chapter

Simplify your preparations for an upcoming exam that covers internal and external environments with help from this entertaining online chapter. Benefit from access to fun lessons, short quizzes and a chapter exam that can effectively enhance and assess your knowledge of this subject.

Internal & External Environments - Chapter Summary

The lessons in this chapter can provide you with a comprehensive overview of internal and external environments. Access the lessons anytime and review them at your own pace to boost your knowledge of homeostasis, body temperature regulation, the pH scale and more. When finished, you will be prepared to do the following:

  • Share the definition of metabolism and discuss its process
  • Define enzymes and the enzyme-substrate complex
  • Describe the pH scale and the optimum pH for enzymes
  • Explain the meaning of homeostasis
  • List functions of the nervous system
  • Detail the process of body temperature regulation in animals
  • Discuss how plants respond to environmental stimuli and stress
  • Differentiate between the responses to change of endothermic and ectothermic animals

Get started by selecting your first lesson and watching the video or reading through the text. Take the accompanying quiz to find out how much you understand. When ready, scroll along the right-hand sidebar to choose other lessons in any sequence and take their quizzes. Check your progress through the chapter and submit lesson topic questions to our experts using the Dashboard. To gauge your grasp of internal and external environments, be sure to take the practice chapter exam.

10 Lessons in Chapter 5: Internal & External Environments
Test your knowledge with a 30-question chapter practice test
Metabolism: Definition & Overview

1. Metabolism: Definition & Overview

Metabolism is the sum of all chemical reactions within the body. This concept, however, is much more complex than most of us understand. This lesson describes metabolism and the processes involved.

What are Enzymes? - Definition & Explanation

2. What are Enzymes? - Definition & Explanation

In this lesson, you will discover what enzymes are, explore how they work, and learn why they're needed for your cells' day-to-day functions. The lesson concludes with a quiz to test your knowledge.

Enzyme-Substrate Complex: Definition & Overview

3. Enzyme-Substrate Complex: Definition & Overview

Enzymes are almost everywhere in your body. Discover where they are found, how they work and why they are important. Learn two models for how the enzyme-substrate complex is formed as well as the changes that could cause this bonding to fail.

The pH Scale: Calculating the pH of a Solution

4. The pH Scale: Calculating the pH of a Solution

Learn the history of the pH scale, how to describe it and why it is used by scientists. Discover how to calculate the pH of an acid or base solutions given either the hydroxide ion concentration or the hydronium ion concentration. Learn how to start with the pH and calculate the hydroxide and hydronium ion concentrations.

Optimum pH for Enzymes

5. Optimum pH for Enzymes

This lesson reviews what pH is and what different pH levels mean. It also gives a brief definition of enzymes and discusses what is meant by optimum pH and how it relates to enzymes.

What Is Homeostasis? - Definition & Examples

6. What Is Homeostasis? - Definition & Examples

Homeostasis can be defined as a property of an organism or system that helps it maintain its parameters within a normal range of values. It is key to life, and failures in homeostasis can lead to diseases like hypertension and diabetes.

Functions of the Nervous System

7. Functions of the Nervous System

In this lesson, we'll watch Timmy as he plays in his backyard. Watch what happens when he tries to catch a butterfly, hears a mean dog bark, and scrapes his knee. All of Timmy's reactions are tied to his nervous system. For a full explanation of what goes on in the human nervous system, check out the video!

Body Temperature Regulation in Animals

8. Body Temperature Regulation in Animals

Animals have different ways of regulating their body temperatures, as well as different sources of body heat. In this lesson, we'll explore both how animals heat their bodies and how they control their internal temperatures.

Environmental Stimuli & Stress: Plant Adaptations & Responses

9. Environmental Stimuli & Stress: Plant Adaptations & Responses

Plants get stressed out about a lot of stuff, like floods, droughts, high heat, and cold. And they have ways in which they deal with these kinds of stress. This lesson gives some examples of how this occurs.

Ectothermic & Endothermic Animals of Australia

10. Ectothermic & Endothermic Animals of Australia

The Australian outback is a dangerous place filled with extreme temperatures. Today, we'll look at how different animals tackle the task of temperature regulation. We'll study two main classes: ectothermic and endothermic animals. You might be surprised by some of the unique ways animals regulate their temperature.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
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