Calcium Homeostasis

by Greg Crowther

This jingle, originally written for Biology 241 at South Seattle College, summarizes the classic textbook view (now somewhat outdated) of how the body uses negative feedback to maintain plasma calcium levels within a desired range.

When plasma calcium is high,
The thyroid sends out calcitonin, yeah!
When plasma calcium is low,
The parathyroid gland gets goin', yeah!

When plasma calcium is high,
There's less intestinal absorption, yeah!
When plasma calcium is low,
The kidney saves a greater portion, yeah!

• 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) How does the melody of this song reinforce its meaning?

(2) What hormone does the parathyroid gland produce, and what does it do to bones?

(3) According to the song, which hormone promotes intestinal absorption of calcium?

(4) Which renal process -- filtration, secretion, or reabsorption -- is adjusted to allow the kidney to "save a greater portion" of the calcium?

(5) Researchers such as A.O. Hoff et al. (Journal of Clinical Investigation 110: 1849-57, 2002) have shown that calcitonin knockout mice have higher-than-normal bone mass in some cases. Are those data consistent with the predictions you would make based on the lyrics of this song?