A lot of physiology involves uncovering and understanding relationships between variables (e.g., when this goes up, that goes down). Here is a two-part song covering two such sets of relationships: those governing feedback control of ventilation, and those governing hemoglobin's affinity for oxygen. Depending on your learning goals, you could focus only on the chemoreceptor part, or only on the hemoglobin affinity part, or both.
[Part 1: chemoreceptor control of ventilation]
Breathing rate and metabolic rate closely correlate,
That information is poured
Ventilation's up (up!)
[Part 2: the Bohr effect]
Hemoglobin is cooperative, binding oxygen
Binding strength will rise and fall.
Affinity goes up (up!)
• MP3 (demo)
• 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) The song opens with the line, "Breathing rate and metabolic rate closely correlate." What does this mean?
(2) Where in the body are these chemoreceptors located?
(3) If you aren't breathing enough to keep up with your body's metabolism, what will happen to the levels of CO2 and H
(4) The end of the first part of the song mentions setpoint and negative feedback. How does this specific example fit the general pattern of homeostasis via negative feedback? What is/are the regulated variable(s) here?
(5) At sea level, is ventilation rate more sensitive to changes in PCO2 or changes in PO2?
(6) What is meant by the line that hemoglobin binds oxygen "in a sigmoid fashion"?
(7) When temperature increases and PCO2 increases, does the hemoglobin-oxygen curve shift to the left or to the right?
(8) How does the Bohr effect improve oxygen delivery to exercising muscles?(Answers may be found on the answers page.)