The Biology course is a first-year course in biology at the high school level and involves the scientific study of living organisms. The course considers the interactions among the vast number of organisms that inhabit planet Earth. It presents the basic form and function of these organisms, from cells to organ systems, from simple viruses to complex humans. It delves into interactions between organisms, and between an organism and its environment. It also looks into how biotechnology is used to improve our health and daily lives.

- Understand the form and function of microorganisms
- Understand the form and function of plants
- Understand the form and function of animals
- Understand the workings of human biological systems
- Understand biology as it relates to the Earth's environment

CK-12 Biology I - Honors is a high school FlexBook covering five units: Cell Biology, Genetics, Evolution, Ecology, and Physiology.

A work in progress, CK-12 Biology I Honors - Teacher's Edition complements CK-12''s Biology I Honors book covering: Introduction to Life Science; Cells; Genetics; Evolution; Ecology; and Human Biology.

A work in progress, CK-12 Biology I Honors Workbook complements its Biology I Honors FlexBook covering: Introduction to Life Science; Cells; Genetics; Evolution; Ecology; and Human Biology.

In this activity, students use a simple pH indicator to measure how much CO2 is produced during respiration, at rest and after exercising. They begin by comparing some common household solutions in order to determine the color change of the indicator. They review the concepts of pH and respiration and extend their knowledge to measuring the effectiveness of bioremediation in the environment.

Submitted as part of the California Learning Resource Network (CLRN) Phase 3 Digital Textbook Initiative (CA DTI3), CK-12 Foundation’s high school Biology I - Honors FlexBook covers Cell Biology, Genetics, Evolution, Ecology, and Physiology.

In this unit, students look at the components of cells and their functions and discover the controversy behind stem cell research. The first lesson focuses on the difference between prokaryotic and eukaryotic cells. In the second lesson, students learn about the basics of cellular respiration. They also learn about the application of cellular respiration to engineering and bioremediation. The third lesson continues the students' education on cells in the human body and how (and why) engineers are involved in the research of stem cell behavior.

In this lesson, students learn about the basics of cellular respiration. They also learn about the application of cellular respiration to engineering and bioremediation. And, students are introduced to the process of bioremediation and several examples of how bioremediation is used during the cleanup of environmental contaminants.

Two lessons and their associated activities explore cellular respiration and population growth in yeasts. Yeast cells are readily obtained and behave predictably, so they are very appropriate to use in middle school classrooms. In the first lesson, students are introduced to yeast respiration through its role in the production of bread and alcoholic beverages. A discussion of the effects of alcohol on the human body is used both as an attention-getting device, and as a means to convey important information at an impressionable age. In the associated activity, students set up a simple way to indirectly observe and quantify the amount of respiration occurring in yeast-molasses cultures. Based on questions that arise from this activity, in the second lesson students work in small groups as they design and execute their own experiments to determine how environmental factors affect yeast population growth.

Students set up and run the experiments they designed in the lesson Population Growth in Yeasts, using simple yeast-molasses cultures in test tubes. Population growth is indicated by the amount of respiration occurring in the cultures, which in turn is indicated by the growth of carbon dioxide bubbles trapped within the culture tubes. Using this method, students can test for a variety of environmental influences, such as temperature, food supply, and pH.

Physiology is the study of the processes of the body. This course is about the unconscious mechanics of living; the student will look at each organ system in detail and then discuss the ways in which the systems interact in order to maintain the body at an optimal state. Metabolism and homeostasis--or the maintenance of the body at a set, optimal level--will be the primary themes. Upon successful completion of this course, the student will be able to: describe the relationship between structure and function at the cellular level and relate dysfunctional states of health to problems at the cellular level when appropriate; given relevant physiological information, explain the physiological mechanisms involved; describe the concepts of homeostasis and feedback control in relationship to each organ system; use a vocabulary of physiological terms and demonstrate an ability to communicate efficiently in a medical environment; describe techniques currently in use that measure the function of organ systems. (Biology 304)

This illustration from Biology by Kenneth R. Miller and Joseph Levine describes the steps of the Krebs cycle, the critical first stage in the process of cellular respiration.

Honeybees provide a convenient source of insect flight muscle, a tissue especially rich in mitochondria. These organelles are easily isolated using simple laboratory equipment and their metabolic activity readily measured colorimetrically with the dye 2,6-dichloroindophenol, which changes from blue to colorless when reduced by the electrons produced during respiration. This system is well-suited for studying cell fractionation, experimental isolation of the major subcellular components responsible for glycolysis and the Krebs cycle, and the role of oxygen in respiration. It can also be used for simple enzymology experiments using the Krebs cycle enzyme succinic dehydrogenase.

This lesson covers the process of photosynthesis and the related plant cell functions of transpiration and cellular respiration. Students will learn how engineers can use the natural process of photosynthesis as an exemplary model of a complex yet efficient process for converting solar energy to chemical energy or distributing water throughout a system.

Students are presented with information that will allow them to recognize that yeasts are unicellular organisms that are useful to humans. In fact, their usefulness is derived from the contrast between the way yeast cells and human cells respire. Specifically, while animal cells derive energy from the combination of oxygen and glucose and produce water and carbon dioxide as by-products, yeasts respire without oxygen. Instead, yeasts break glucose down and produce alcohol and carbon dioxide as their by-products. The lesson is also intended to provoke questions from students about the effects of alcohol on the human body, to which the teacher can provide objective answers.