Intermediate Biology
About this free Intermediate Biology course
Intermediate Biology is a free high school biology course that goes beyond the basics to explain how life works at the molecular and cellular level. It's designed for high school students and beyond, and its eight structured core units follow the same big topics as AP Biology, making it a strong preparation or review course.
The course starts with the foundations of biology and the scientific process, then moves to the chemistry of life, cell structure, cellular energetics, the cell cycle and communication, heredity, gene regulation, natural selection, and ecology. Detailed explanations and illustrated examples walk through complex processes like photosynthesis, cellular respiration, and gene expression step by step, preparing students for advanced studies in the life sciences.
Who this course is for
This course is designed for high school students in grades 10 through 12 who have completed an introductory biology course. It's especially useful for students taking AP Biology or preparing for college life sciences. Some basic chemistry helps with the early units.
Course outline
- Unit 0: Foundations of biology. The characteristics of life and the scientific process.
- Unit 1: Chemistry of life. Water, elements, and the structure and function of macromolecules.
- Unit 2: Cell structure and function. Organelles, membranes, and transport across the cell membrane.
- Unit 3: Cellular energetics. Enzymes, photosynthesis, and cellular respiration.
- Unit 4: Cell communication and the cell cycle. Signal transduction, feedback, mitosis, and cell cycle regulation.
- Unit 5: Heredity. Meiosis, Mendelian genetics, and patterns of inheritance.
- Unit 6: Gene expression and regulation. DNA replication, transcription, translation, and gene regulation.
- Unit 7: Natural selection. Evolution, evidence for common ancestry, and population genetics.
- Unit 8: Ecology. Energy flow, populations, communities, and ecosystems.
What you'll learn
- Relate the structure of biological molecules to their function
- Explain how cells capture and use energy through photosynthesis and respiration
- Describe how cells communicate and control the cell cycle
- Predict inheritance patterns and explain how genes are expressed
- Connect natural selection and ecology to changes in populations
How long it takes
Plan on about 25 hours, or roughly three hours per unit. Cellular energetics and gene expression are the densest units, so budget extra time for them.
Frequently asked questions about Intermediate Biology
Is Intermediate Biology really free?
Yes. Intermediate Biology is completely free, with no fees, subscriptions, or account required. STEM for Others is a 501(c)(3) nonprofit, and every course in our curriculum library is free for students, families, and teachers.
Does this course follow AP Biology?
Its eight core units line up with the eight units of the AP Biology course framework, from chemistry of life to ecology. It isn't an official AP course, so pair it with College Board practice questions.
How do I start the course?
Click Begin Course at the top of this page to open the full slide deck in a new tab. You can also flip through the slides embedded above. Work through one unit at a time and try the practice questions before moving on.
Do I get a certificate?
The self-paced Intermediate Biology materials don't include an official certificate. If you're taking the course through a STEM for Others chapter program, ask your chapter leader about recognizing your completion.
Can teachers and clubs use this curriculum?
Yes. Teachers, homeschool families, libraries, and after-school clubs are welcome to use the Intermediate Biology materials with their students at no cost. STEM for Others volunteers also teach our curriculum in partner schools and libraries. You can find a chapter near you or start one at your school.
