Helping Students See the Big Picture

Teaching thousands of anatomy and physiology students over the decades has taught me that a major hurdle is being able to see the "big picture" of the structure and function of the human body.

Because the A&P course necessarily includes a nearly overwhelming collection of detailed, technical facts expressed in a language that is foreign to many beginning students, they become so focused on each bit of information that they have hard time putting it all together into a coherent conceptual framework.  

One approach would be to present a concept map—or some type of graphic representation—of all the core concepts of each body system.  For example, a graphic showing how the system explored in a particular chapter ties into the structure and function of all the other systems of the body.

I think a graphic approach can be very useful, but I wonder if that strategy isn't better used as an active learning exercise in which each learner creates their own concept map—perhaps after some of the initial learning of a topic has already taken place.  Or, even better, make it a collaborative study project among a group of peers. 

I think a better approach in a textbook with limited page space is to build a "big picture" perspective into the narrative of the story.  So that's why in Anatomy & Physiology we have included a highlighted section at the end of each chapter that briefly pulls the reader back from the details of the chapter and widens the focus to take in a bigger, more global perspective.

Called The Big Picture, this feature does several things:

• It calls the reader's attention to a whole-body, integrated view of the current topic's place in the wider scheme of human structure and function.


• It gives specific examples of  how the current topic relates to—or builds upon—concepts covered in previous chapters.  This encourages students to integrate new concept with their growing framework of of knowledge to construct a solid  understanding of A&P.


• This feature also looks ahead to concepts of later chapters by mentioning how the current topic will lead to a fuller understanding of concepts yet to be explored in the A&P course.


• It improves reading comprehension of each chapter by calling attention to the main themes and reminding the reader of core concepts within a meaningful context.


• The Big Picture specifically relates the current topic such core principles as homeostasis and form-fits-function.


• Besides outlining specific examples of connections among concepts, The Big Picture also asks students to think about the integration of concepts themselves—thus encouraging them to develop the critical thinking skills needed to take their A&P learning forward into later courses (and into their professions).

To get the reader's attention, a one-page introduction called Seeing The Big Picture faces the first page of Chapter 1 of Anatomy & Physiology.  This feature grabs the readers attention immediately and sets them along their path already looking for the big picture.  It encourages students to think about relationships as they read—but also tells them to look for The Big Picture at the end of each chapter to help them "get" the big ideas of the chapter.

We have given a lot of thought to which strategy works best to help readers understand whole-body relationships. We are certain that the tried-and-tested summary narrative The Big Picture works well in stimulating critical thinking and construction of a solid conceptual framework than a pre-constructed chart that may short-circuit the learning process in a learner's mind.

Got Proteasomes?

For several editions, Anatomy & Physiology has featured a brief description of the structure and function of proteasomes in the cell.  As several recent papers in Science, Nature, and other journals point out, understanding the proteasome is critical to understanding how the cell handles protein—a "big idea" in the A&P course.

Beyond that, dysfunctions in the ubiquitin-proteasome system (UPS) have been implicated in a wide variety of important health conditions, including neurodegenerative diseases (e.g., Alzheimer disease, Parkinson disease), drug addictions, learning disorders, cardiovascular disease, immune dysfunctions, and others.  Manipulation of the UPS has been proposed for various medical therapies, as well.

For example, the drug bortezomib (Velcade) is a proteasome inhibitor used to treat some adults with multiple myeloma.

So given the central role of the proteosome, why is this vitally important organelle left out of most A&P textbooks?  Really, I'm asking.  Because I can't think of a good reason.

Besides its emerging role in understanding major diseases and therapeutic strategies, the proteosome gives students a more complete picture of the cell as a "protein factory." It helps integrate the whole protein synthesize story with the basic concepts of amino acids and protein folding learned earlier in the course.  Not to mention the homeostasis of amino acid balance in cells.

The proteasome story can be told simply, so there's no reason to leave it out for the reason that "it's just too much detail" for a beginning student to handle.  Check out this resource intended for high-school students: The Proteasome.

Anatomy & Physiology features a short, illustrated description of the ubiquitin-proteasome system that easily integrates with the bigger picture of protein handling in the cell.  It's on page 85 of the new 9th edition.  Now you know why I included it!

Homeostasis Deserves Its Own Chapter

Homeostasis is a major theme of every anatomy and physiology course, so why not explore this important principle in a single, focused chapter?

In a recent post, I explained my rationale for chunking Anatomy & Physiology into smaller chapters than are typical among A&P textbooks.  This provides the opportunity to devote a single, compact chapter to the concept of homeostasis.

Starting in the upcoming 9th edition, the second chapter of Anatomy & Physiology is devoted solely to describing the concept of homeostasis and explaining its central role in maintaining normal function of the human body.  This comes after a brief introductory chapter outlining the nature of the human life sciences and the organization of the body.

This reorganization also provides the opportunity to chunk the sections and provide headings and subheadings that help readers understand how various aspects of homeostasis "hang together."

• Homeostasis
• The Internal Environment
• Relative Stability
• Set Point
• Models of Homeostasis
• Homeostatic Control Mechanisms
• Feedback Loops
• Basic Components of Control Systems
• Sensor
• Integrator
• Effector
• Feedback
• Negative Feedback in Control Systems
• Positive Feedback in Control Systems
• Changing the Set Point
• Feed-Forward in Control Systems
• Levels of Homeostatic Control
• Summary of Homeostasis
• Cycle of Life: Life Span Considerations
• The Big Picture: Homeostasis
• Mechanisms of Disease
• Basic Mechanisms of Disease
• Risk Factors
• Case Study

By focusing on homeostasis and the underlying role it plays in nearly all body functions in this manner, students "get it" in a way that helps them move into the remainder of their A&P course with clearer understanding of the big picture.

A few other improvements to coverage of homeostasis in this newly formed chapter include:

Concepts

• A brief discussion of circadian rhythms helps students better understand that set points can change in a daily pattern, thus preparing them for such patterns encountered in later chapters
• Clarification that feedback loops can be understood as stimulus-response mechanisms, which helps students apply homeostatic principles to nervous system applications

Learning Objects

• A new table listing homeostatic functions of each major body system helps students better visualize the global aspects of homeostasis
• New set of graphs showing circadian cycles in various physiological variables helps students visualize an important concept, while also introducing them to interpretation of physiological graphs
• A new diagram representing disease as a loss of homeostatic balance helps student understand the role of homeostasis in health and disease
• A new case study helps students practice applying concepts of homeostasis to clinical examples

Examples

• More examples of negative-feedback mechanisms, positive-feedback control, feed-forward regulation help students better understand and apply these concepts
• The model of a tightrope walker (Wallenda model) was added to illustrate concepts of homeostasis missed by the engineered control system model and the fishbowl model of homeostasis
• A cross-reference to the new A&P Connect article The Human Microbiome helps students integrate the concept of microbial function with the functions of human organs and systems.
• New boxed content on negative feedback during exercise helps students apply concepts of homeostatic regulation to real-world situations

Photo: topfer (freeimages)