As instructors of introductory biology courses for majors and non-majors, we have struggled with teaching the concept of cell structure and function in an engaging way.  However, this is a foundational concept that most biology instructors would agree is vital for all students to know. The overall objective of this teachable unit is to help non-major introductory biology students learn the names and functions of the basic components of eukaryotic cells and, at the same time, understand the connection between cellular structure and function using active learning approaches. The key component of this teachable unit is a group exercise termed Cell Engineer/Detective. In this exercise, students work in groups to design a cell that is well suited for a function that is provided to them by the instructor (Cell Engineer). The groups then exchange their cells with classmates and try to guess the function of their classmates’ cells (Cell Detective). This exercise helps students visualize how the organelles of a cell work together to perform a specific function, allows instructors to clarify misconceptions regarding cell structure, guides students away from that quintessential but unrealistic model cell found in most biology textbooks, and reinforces the central biological connection between form and function.

Read the Essay Article about how author HN Tinsley adapted this lesson for online in "Online Adaptation of the Cell Engineer/Detective Lesson"

This module introduces the Dixon equation in the context of understanding nutrient transport through sieve tubes. It is intended for an introductory biology audience.

This module introduces the Poiseuille equation in the context of understanding nutrient flow in plant cells. It is intended for an introductory biology audience.

One of the major learning objectives established by the American Society of Plant Biologists and the Botanical Society of America has students answer the question: How do plant structures enable life functions? This lesson helps students answer this question with a focus on leaf structure and function and how the anatomy and morphology of the leaf optimizes photosynthesis and promotes survival in various environments. Students are first introduced to the primary structures and cell layers of a typical angiosperm leaf, including differences between monocots and dicots, through an interactive mini-lecture. Then, students in groups are asked to design a leaf based on a provided description. These descriptions include a monocot or dicot designation and specific environmental conditions to which the leaf is adapted. After the leaves have been designed, they are collected and redistributed to new groups. These groups are then asked to analyze the leaf they've been given, determine if it is a monocot or dicot, and determine the environment where this leaf would thrive. Finally, students present and defend their findings to the class. This lesson engages students in leaf structure and function as a means to optimize photosynthesis and promote survival and prepares them for future lessons on photosynthesis and evolution.

Algae are a fascinating and diverse organismal group, with global ecological importance, a storied evolutionary history and deep connections to both contemporary and historical human societies. Yet non-experts who teach algal diversity face a lack of examples in many general biology textbooks and the difficulty of generalizing a group that includes many distantly-related lineages that don't share a single common ancestor. This lesson embraces the complexity of algae using a sorting game and tree-building activity. Students work in groups to decide which organisms from a provided set are eukaryotic algae. The class creates consensus statements about what exactly defines organisms as "algae" and self-discover that exceptions exist for every seemingly definitive algal trait. Students then build simple phylogenetic trees and map their organisms across the phylogenetic Tree of Eukaryotes in order to explore the complex evolutionary relationships between the major eukaryotic algal lineages. Student written responses recorded before and after the sorting game indicate students become more nuanced and expert-like in their descriptions of algae. This lesson is an engaging way to introduce students to algae and can be modified for a variety of courses including high school, non-majors biology courses and introductory biology courses.

Primary image: A photo of the phylogenetic trees made by students during the tree-building activity. Photo taken by the author, B. Clarkston.