Common Misconceptions in Biology Class and Why It's Important to Correct Them

A misconception is an inaccurate or incomplete understanding of a concept held by a student. Misconceptions can arise from misapplication of prior knowledge, misinterpretation of everyday experiences, or even inaccurate teaching. We must correct misconceptions because they can hinder students' learning accurate science concepts and may persist into adulthood. By addressing and correcting misconceptions, students can develop a more robust understanding of scientific concepts and build a strong foundation for further learning.

Inquiry-based lessons effectively address misconceptions in the science classroom because they engage students in active learning, allowing them to test their own ideas and understandings. By encouraging questioning and exploration, these lessons empower students to confront and resolve their misconceptions through direct experience and investigation. This approach also promotes critical thinking and a deeper understanding of scientific concepts. The key is to know which misconceptions to address in a lesson.

Below you will find the 5 most commonly held misconceptions I see in my high school biology students:

Misconception 1: "Atoms can be destroyed during chemical reactions that involve fire."

Reality: Atoms cannot be created or destroyed during chemical reactions.

Misconception 2: "Atoms are heavier when solid and lighter when gaseous"

Reality: A particular atom has the same mass whether it is in a solid, liquid, or gaseous state.

Misconceptions 1 and 2 are closely related and can prevent students from developing an accurate understanding of cellular respiration and photosynthesis. For example, students may fail to realize that a tree gains mass during photosynthesis as the atoms from carbon dioxide in the air are used to build sugars in the plant. They may believe that gases like air have no mass and may inaccurately attribute the plant's growth to soil or only water. I have found that presenting a discrepant event involving the masses of solids and gases, as well as modeling chemical reactions with tangible manipulatives such as Legos, helps students overcome these misconceptions. You can check out the BioDistilled Cellular Respiration and Photosynthesis Units to see how I design lessons to address these misconceptions.

Misconception 3: "Cells in the human body that appear different from each other contain different DNA."

Reality: All the cells in a person's body contain the same DNA in their nucleus (with a few exceptions including sperm, egg cells, and red blood cells), but they express different genes.

You can check out the BioDistilled DNA, Division, and Differentiation Unit to see how I design lessons to address this misconception.

Misconception 4: "Girls inherit their mother's traits, and boys inherit their father's traits."

Reality: Children inherit an equal amount of DNA from their two biological parents. However, the traits expressed are influenced by the combination of inherited alleles. Some alleles are dominant, while others are recessive. A dominant allele has a greater influence over the expression of a trait than a recessive allele in cases of complete dominance.

You can check out the BioDistilled Meiosis and Heredity Unit to see how I design lessons to address this misconception.

Misconception 5: "Individuals decide which traits they need to evolve to survive."

Reality: Traits that provide a survival advantage tend to increase in a population over multiple generations due to natural selection.

You can check out the BioDistilled Biological Evolution Unit to see how I design lessons to address this misconception.

It's important to note that students hold far more misconceptions than the five listed above. We need to uncover and address these misconceptions too! Below, I describe my favorite techniques for identifying and overcoming them.

Identifying Misconceptions:

Teachers can identify students' misconceptions using diagnostic assessments and probing questions.

A diagnostic assessment is a type of evaluation used to assess a student's current knowledge and skills before a unit of instruction. Teachers can create multiple-choice questions with distractor options to identify misconceptions and determine if their students have them. The key is knowing what these misconceptions are. BSCS has a website that contains a database of common misconceptions about science concepts, available on their website here:

Alternatively, teachers can create open-ended questions tailored to uncover these misconceptions. By reviewing the responses, it becomes evident which misconceptions are most common among students in a class and need to be addressed. Administering a diagnostic assessment before a unit of instruction begins allows teachers to design lesson sequences that target commonly held misconceptions. Example diagnostic assessments, including both open-ended and multiple-choice style questions, are available for free from BioDistilled here:

Teachers can also use probing questions during the Engage portion of a 5E science lesson to uncover misconceptions. Although asking questions at the start of a lesson doesn't allow teachers to plan ahead, it does provide the opportunity to make on-the-fly decisions about addressing individual students' misconceptions at the right time. Beginning a lesson with thought-provoking questions also allows students to reflect on their initial beliefs and witness how their perspectives evolve by the end of the lesson.

Overcoming Misconceptions:

Two effective ways to help students overcome misconceptions are through the use of discrepant events and by asking students to explain why an incorrect response, containing the targeted misconception, is wrong.

A discrepant event is a demonstration or experiment that shows unexpected or surprising results, challenging students' preconceived notions and leading to a "discrepancy" between their expectations and actual outcomes. For instance, in a science lesson about the conservation of matter, a discrepant event might involve measuring the mass of dry ice before and after it sublimates. Since solid and gaseous states of carbon dioxide contain the same number of atoms, the mass of dry ice and its gaseous form are the same. This unexpected result can prompt students to question their initial assumptions and engage in discussions about the scientific principles behind the phenomenon.

Encouraging students to analyze and critique incorrect answers fosters engagement with scientific concepts and promotes the recognition of flaws in misconceptions. For example, asking students to explain why the statement "a balloon filled with air is lighter than an empty balloon" is incorrect prompts students to identify common misunderstandings, promoting deeper understanding through discussion and explanation of correct principles.

By addressing misconceptions head-on, educators can foster a more accurate and robust foundation of scientific knowledge, enhancing students' critical thinking skills. Engaging with student misconceptions allows for targeted and personalized instruction, leading to a deeper comprehension of scientific concepts. Using these and other techniques, science teachers can create an inclusive and supportive learning environment where students feel empowered to challenge and revise their preexisting beliefs, ultimately promoting genuine and enduring learning outcomes.