About This Chapter
Praxis Biology: Molecular Structure Basics - Chapter Summary
The lessons in this chapter help you explain the structure of molecules and include a look at the atom and its parts. You will learn about various types of chemical bonds. Another lesson explores the properties of water, such as cohesion and high specific heat. By the end of this chapter, you should be prepared to answer Praxis exam questions concerning these topics:
- The electron shell
- Chemical bonds: covalent, ionic, polar covalent and hydrogen
- Solutions, solutes and solvents
- Osmosis, diffusion and saturation
- Acids and bases
- The laws of thermodynamics
Experienced instructors teach these lessons, using examples to illustrate many topics. With these concise, fun lessons, you will gain the information you need to correctly answer the questions on the Praxis Biology exam. The quizzes at the end of each lesson enable you to test your knowledge, and the links included in the videos enable you to easily locate and re-watch key points in the lessons.
Objectives of the Praxis Biology: Molecular Structure Basics Chapter
Many states mandate that applicants for teacher certification pass the Praxis examination in the subject they wish to teach. The Praxis Biology: Content Knowledge exam contains 150 multiple-choice questions that cover what a teacher of biology at the secondary school level should know. The test has a two-hour time limit and is available on paper or computer. It has six sections, and questions on the material contained in the Molecular Structure Basic chapter are in section II, Molecular and Cellular Biology. This section, with 38 questions, makes up about 25% of the total test.
1. The Atom
Tune into this lesson to find out what matters about matter. What exactly is an atom? And, how do the atoms that make up the elements in the periodic table differ from one another?
2. The Electron Shell
You may be familiar with the role of electrons in electrical devices, but did you know that electrons also determine the chemical reactivity of everything around you?
3. Chemical Bonds I: Covalent
Mom always said that sharing is caring. This lesson will explore how electrons affect the chemical reactivity of atoms and specifically the merits of sharing electrons.
4. Chemical Bonds II: Ionic
Did you know that the scientific name for table salt is sodium chloride? Find out how sodium and chlorine atoms come together to form your favorite seasoning.
5. Chemical Bonds III: Polar Covalent
Are you confused about how you can tell what kind of bond two atoms will form? This lesson will help you understand the difference between polar and nonpolar covalent bonds as well as how to predict how two atoms will interact.
6. Chemical Bonds IV: Hydrogen
This lesson defines and discusses important concepts behind hydrogen bonding. You'll learn when and why these bonds occur and which atoms are often involved.
7. Properties of Water
Why does ice float? Why can water rise on its own against gravity in a small tube? Find out how these mysterious properties of water can be explained by hydrogen bonds.
8. Solutions, Solutes, and Solvents
Oh no! Your friend Ben just drank chili oil on a dare, and now his mouth is burning. Should he drink the ice water or vegetable oil to cool his mouth? Quick. Watch this lesson if you aren't sure.
9. Osmosis, Diffusion and Saturation
The cells in our bodies are in constant flux through the processes of osmosis and diffusion. Learn about how saturation levels force change, and why we're lucky they do.
10. Acids and Bases
Have you ever wondered how we measure the acidity of liquids? Check out this lesson to see how acids and bases are measured on a pH scale and how they relate to neutral solutions, such as water.
11. The Laws of Thermodynamics
Learn about the first and second laws of thermodynamics. Find out how energy is generated, how it converts from one form to another, and what happens to energy in a closed system.
Earning College Credit
Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.
To learn more, visit our Earning Credit Page
Transferring credit to the school of your choice
Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.
Other chapters within the Praxis Biology (5235): Practice & Study Guide course
- Praxis Biology: Science Principles - Processes and Disciplines
- Praxis Biology: Science Principles - Hypotheses, Theories and Change
- Praxis Biology: Science Principles - Numbers
- Praxis Biology: Science Principles - Interpretation and Models
- Praxis Biology: Laboratory Safety
- Praxis Biology: Laboratory Equipment & Measurements
- Praxis Biology: Chemical Reactions
- Praxis Biology: Biological Molecules and Processes
- Praxis Biology: Cellular Energy Flow
- Praxis Biology: Cell Structures and Functions
- Praxis Biology: Cellular Division
- Praxis Biology: DNA and Replication
- Praxis Biology: RNA and Gene Expression
- Praxis Biology: Mutations and Other Genetic Changes
- Praxis Biology: Biology Lab Techniques
- Praxis Biology: DNA Technology
- Praxis Biology: Genetics and Inheritance
- Praxis Biology: Human Genetics
- Praxis Biology: Species, Populations and Evolution
- Praxis Biology: Origin of Life on Earth
- Praxis Biology: Classification of Organisms
- Praxis Biology: Human Anatomy and Physiology
- Praxis Biology: Immunology
- Praxis Biology: Animal Reproduction and Development
- Praxis Biology: Plant Biology
- Praxis Biology: Plant Reproduction & Growth
- Praxis Biology: Population Ecology
- Praxis Biology: Ecosystem Ecology
- Praxis Biology: Human Impacts on the Environment
- Praxis Biology: Environment and Society
- Praxis Biology Flashcards