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.

An appreciation of organismal diversity is a requirement for understanding evolution and ecology, and can serve as a source of amazement and wonder that inspires students to enjoy biology. However, biodiversity can be a challenging subject to teach: it often turns into a procession of facts to memorize and a disorienting list of Latin names. To help engage students in this topic, we developed an activity in which each student contributes to a class "biodiversity tour" of strange and intriguing species. Students in our large-enrollment introductory biology course use the Internet to find a species that interests them and that they think will interest their peers. They research their species and complete a worksheet to report their findings. Then they meet in discussion sections of ~32 students (in person or online) where each student gives a brief presentation about their species using a slide they have prepared, producing a lively, crowd-sourced, rapid-fire nature documentary. The performance for their peers motivates students to find the strangest species possible. Students overwhelmingly reported that this activity taught them something new about life on Earth and increased their interest in our planet's species. Many students also reported that this activity caused them to talk to someone about biology outside of the class and increased their personal connection to the natural world, suggesting that it helped them see the relevance of biology to their everyday lives. This simple activity can enrich an introductory biology course of almost any size.

Primary image: Photos of some of the species chosen by students in Fall 2019.

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.

Critically reading and evaluating claims made in the primary literature are vital skills for the future professional and personal lives of undergraduate students. However, the formal presentation of intricate content in primary research articles presents a challenge to inexperienced readers. During the fall 2020 semester, I introduced a Collaborative Annotation Project (CAP) into my online 400-level developmental neurobiology course to help students critically read eight research papers. During CAP, students used collaborative annotation software asynchronously to add clarifying comments, descriptions of and links to appropriate websites, and pose and answer questions on assigned papers. Student work was guided and assessed using a CAP grading rubric. Responses to anonymous surveys revealed students found CAP helpful for reading the primary literature and the rubric clarified expectations for the project. Here, I describe how I introduced, used, and assessed CAP in my online class, and I share the detailed CAP instructions and rubric.

Primary image: A moment of levity while annotating primary literature. Sample student annotations from the Collaborative Annotation Project. Student #1 compares immunofluorescence data to Christmas lights, an observation appreciated by student #2. Student names have been removed.