Ch 19: Principles of Life Sciences

About This Chapter

Bring back what you learned about the principles of life sciences by going through this chapter. Use the lessons to get a recap on major terminology related to natural selection, ecosystems, and the parts of a plant as well as to remember the biological processes of living organisms.

Principles of Life Sciences - Chapter Summary

This chapter helps you review all the key areas within the life sciences. Let the lessons provide you with insight about the shared traits of living organisms, environmental factors, physiological processes, and other key details. After you complete this chapter, you should be able to:

  • Describe the defining characteristics and basic needs of living organisms
  • Analyze and explain ecosystems
  • Check out the connection among energy flow, trophic levels, and food chains
  • Define and identify various parts of a plant
  • Examine reactions occurring during photosynthesis
  • Explain the organ systems of the human body
  • Provide a basic overview of genetics
  • Offer examples of adaptation and natural selection
  • Identify types of community ecology

One way to verify how much information you are gaining from this chapter includes using our self-assessment quizzes. Each quiz is equipped with around five selected-response style questions. These questions may test your ability to remember definitions, apply key concepts, recognize important individuals, and more. After you answer the questions, you will know immediately how many answers you got right or wrong. Whenever you score low on a quiz, it may be a good idea to take a closer look at that lesson. You can retake our quizzes to improve your scores or to help you memorize information before an upcoming exam.

10 Lessons in Chapter 19: Principles of Life Sciences
Test your knowledge with a 30-question chapter practice test
The Defining Characteristics of Living Organisms

1. The Defining Characteristics of Living Organisms

A house is not a living thing, but the people, animals, and plants living inside it are. So how do we define 'life'? Learn about seven characteristics that all living organisms have in common, no matter how different they may look on the outside.

Living Organisms: Basic Needs

2. Living Organisms: Basic Needs

There are many types of living organisms on Earth. But what makes us all the same is our basic needs for survival, which is a shorter list than you might think!

What Is an Ecosystem? - Definition & Explanation

3. What Is an Ecosystem? - Definition & Explanation

Similar to a car engine that is made up of multiple parts working together, an ecosystem has interacting parts that support a whole. But how do we define an ecosystem and what are the components they consist of?

Food Chains, Trophic Levels and Energy Flow in an Ecosystem

4. Food Chains, Trophic Levels and Energy Flow in an Ecosystem

In this lesson, you'll learn about food chains, food webs, and the different roles that organisms play in an ecosystem. You'll also learn about how energy flows through an ecosystem.

What are the Parts of a Plant?

5. What are the Parts of a Plant?

Ever look at a plant and wonder what each specific part is? A plant has two basic plant parts: the shoot and root systems. In this lesson, you'll learn and be able to identify each individual plant part within the shoot and root systems.

Photosynthesis: Definition & Reactions

6. Photosynthesis: Definition & Reactions

Some people may falsely assume plants to be weaker than animals. However, plants and a few other organisms harness light energy from the sun to feed the rest of us. This lesson will introduce you to how they do it.

What Are the Organ Systems of the Human Body?

7. What Are the Organ Systems of the Human Body?

In this lesson, you'll learn about the 11 organ systems, which are made of multiple organs that work together to keep the human body functioning. Using easy-to-understand descriptions and illustrations, we'll explore the circulatory, respiratory and digestive, systems, among other types, after which you'll have the chance to take a brief quiz and see how well you understood the material.

Genetics: Heredity, Traits & Chromosomes

8. Genetics: Heredity, Traits & Chromosomes

We view manipulation of genes in our crops and livestock as a recent development. Yet, man has been manipulating the genetic makeup of his food for thousands of years through cultivation and breeding. This lesson will begin to help you understand how genetics works.

Natural Selection & Adaptation: Definition, Theory & Examples

9. Natural Selection & Adaptation: Definition, Theory & Examples

How does natural selection help shape the amazing types of animals we witness around us? In this lesson, we'll explore adaptations and what they can tell us about a species' past evolution.

Community Ecology: Definition & Types

10. Community Ecology: Definition & Types

Community ecology looks at the interactions between populations of organisms. Here we explore a polar ecosystem in Greenland to describe what community ecology entails and what it really means to be at the top of the food chain.

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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