Shine a Light on a Lumen

by Greg Crowther

"Lumen" is a word that anatomy and physiology instructors use all the time in many different contexts, yet students often have no idea what we're talking about. Here is a song to set everyone straight once and for all!

CHORUS:
Shine a light on a lumen;
It's the middle of a tube where a fluid is moving
And surrounded by a lining of epithelium.
But if you are assuming
All lumens are large, then look again and zoom in;
Organelles inside a cell have lumens of their own.

Every artery and each vein: there's a lumen!
The neural tube creating your brain: there's a lumen!
The whole gastrointestinal tract: there's a lumen!
The Golgi, where the proteins are packed: there's a lumen!
The reproductive tract, his and hers: there's a lumen!
The organelle where lysis occurs: there's a lumen!
The bronchi and the small bronchioles: there's a lumen!
Every tube containing a hole: there's a lumen!

CHORUS

• karaoke

• MP3 (demo; with Murph + the Mechanics)

• music video

• sheet music (with melody play-back)

Songs like this one can be used during class meetings and/or in homework assignments. Either way, the song will be most impactful if students DO something with it, as opposed to just listening.

An initial, simple follow-up activity could be to answer the study questions below. A more extensive interaction with the song might entail (A) learning to sing it, using an audio file and/or sheet music as a guide, and/or (B) illustrating it with pictures, bodily poses, and/or bodily movements. The latter activity could begin with students identifying the most important or most challenging content of the song, and deciding how to illustrate that particular content.

(1) What is "the organelle where lysis occurs"?

(2) How does lumen's meaning in biology differ from its meaning in physics?

(3) The song notes that "every artery and each vein" has a lumen. Do capillaries have lumens too?

(4) Epithelial cells that border a lumen have an apical surface and a basolateral surface. Which one faces the lumen?

(5) For a hole or opening to be considered a lumen, does it have to be circular in cross-section?

(6) Is flow through a lumen regulated, or does it just occur at a steady, constant rate?