Biology—the study of living things and their vital processes—is a continuously evolving field. New cutting-edge research in biology constantly sheds more light on how our species and the world around us function. Intro to biology textbooks are mainly used in first-year classes to provide students with the basic knowledge of various life systems and our ecosystem.

Undergraduate students may take biology courses as electives, as pre-med, or they may major in this field in hopes of becoming botanists, zoologists, forensic scientists, or a whole host of other STEM-based roles. Biology textbooks always evolve with research and discovery, and an introduction to biological sciences course is mandatory for entry into other subjects, such as biophysics, zoology, botany, microbiology, biochemistry and many more.

Here, we look at three must-haves for any intro to biology textbook to help students—including those with little to no prior exposure to living systems—learn about cells, molecules, organisms and more.

Cellular biology

Our entire body is composed of cells—the basic unit of all life forms. Any general biology textbook should focus on how the nucleus controls cellular reproduction, how the mitochondria turn nutrients into energy and the transport system’s role in feeding the cell. The cell’s origin can also provide a good foundation for undergraduates to understand how humans came to be. And the beginning of life, from when the Earth consisted of just prokaryotes to current day modern eukaryotes, demonstrates the breadth of evolutionary biology.

An intro to biology textbook should also spend time discussing the most important molecule in our lives, water, especially since our bodies are made up of about 78 percent H2O when we’re born. Water is critical for many important functions including flushing waste, regulating body temperature and pumping oxygen.

It’s important to teach students the basics of cell biology early in their academic careers as it can help explain how certain diseases and disorders come to be—including cancer, which affects nearly one out of three Americans. Understanding how cells work in healthy and diseased states is the first step towards developing more effective vaccines and medicines. Future forensic students, for instance, will use even basic cell and molecular biology in their work; cell and molecular biology, and genetics, can also be used to reveal one’s unknown ancestors and family heritage.

Systems metabolism

Once students are comfortable with the basics of how cells behave, it is important to teach them how a group of cells form together to form organs and biological systems. One example of a biological system is the digestive system—which is found in all living organisms. The digestive tract breaks down nutrients from food and drink into proteins, carbohydrates and lipids for energy, growth and cell repair. It’s necessary for any intro to biology textbook to provide students with the basics of how food transforms into energy—a fundamental component that every living organism depends on to perform just about any task.

Understanding how cells produce energy can reveal how all living things stay alive and function. Diet and lifestyle changes can come from a better understanding of how cells function. Metabolism studies can show how diseases such as diabetes function and in turn, can show what changes humans need to make to avoid these ailments.

Molecular biology

The “code” of all living things—better known as deoxyribonucleic acid (DNA)—is another critical component that intro to biology textbooks should focus on. DNA is the hereditary material in all organisms and can be found in the cell nucleus. DNA also holds all the information needed for protein production. Proteins are essential in many cellular functions. Lectures that focus on DNA also provide a good foundation for students to understand evolutionary biology, or how organisms came to be and have evolved. Tying into previous sections, a molecular biology unit should also touch on mutation and disease, cell division and cancer.

Understanding humans’ embedded “code” is the most important component for students interested in pursuing a career in genomics. Forensic students, once again, must be equipped with the fundamentals of the human genome—especially when it comes time to match or rule out a suspect’s DNA to biological evidence found at a crime scene. Undergraduates must study molecular biology to learn how they can apply the principles of DNA to various science-oriented careers and to learn what sets them apart from those around them.

These are just three of the many components any intro to biology textbook should contain. Top Hat’s interactive intro to biology textbook covers them all, as well as other critical basic topics such as evolution, ecology and dysregulation in systems.

Learn more and get a preview here.