Ch 21: Praxis Biology: Origin of Life on Earth

About This Chapter

Allow us to guide your study for the Praxis II Biology Content Knowledge exam. You can learn some of the scientific theories of how life on Earth may have begun through informative video lessons with quizzes.

Praxis Biology: Origin of Life on Earth - Chapter Summary

You can review the four basic stages widely accepted by scientists as to how non-living things could have turned into life. Meet A. I. Oparin, Harold Urey and Stanley Miller, and find out about their hypotheses and experiments.

You can also learn the theories of evolution, formed by both geologists and biologists, which portray wide patterns of change over many years. Examine the endosymbiotic theory, the panspermia hypothesis and the RNA world hypothesis. Get ready for the Praxis II Biology Content Knowledge exam by studying the following topics:

  • Theories and explanations of the beginnings of life on Earth
  • Key contributors to the study of evolution and the origins of life on Earth
  • Main periods of change in Earth's history
  • Effects of biological conditions on the composition of the atmosphere
  • Evolutionary change

You can watch the video lessons, read the written transcripts and complete the short quizzes at the end of each lesson. The videos include tags that can help you quickly locate certain portions of the presentations for further review.

Praxis Biology: Origin of Life on Earth Objectives

Approximately 23 questions, or 15% of the entire exam, relate to the topics in this chapter. To prepare for this portion, you'll probably want to review the basics of evolution and different scientific accounts of how life on Earth may have begun, in addition to the various types of evidence that give strength to the theories and hypotheses. All of the test questions are multiple-choice. Our experienced teachers provide well-crafted quizzes at the end of each lesson, which can be a definite advantage towards your successful review for test day.

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.
Not Taken

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