lyrics by Greg Crowther and Monty Harper; sung to the tune of "Loch Lomond" (traditional)
This is a song of farewell from the perspective of a chromatid about to separate from her sister chromatid during mitosis. It includes references to DNA polymerases (which synthesize new strands of DNA, using existing strands as templates), the mitotic spindle (which guides the chromosomes toward the opposite ends of the soon-to-be-dividing cell), the equatorial plane (where chromosomes line up during metaphase), centromeres (the region of the chromosome where sister chromatids are linked), anaphase (the stage of mitosis that follows metaphase), and the fact that the cell's nucleus dissolves during prophase (after DNA replication during interphase by the enzyme DNA polymerase). It was written as a goodbye song for the students and staff of St. John Catholic School in December of 2017.
It wasn't long ago
That we said our first "hello";
Polymerases built us out of bases.
But time is marching on;
Now the nucleus is gone,
And the two of us are bound for different places.
You'll take the left road,
And I'll take the right road,
For that is how the mighty spindle pulls us.
And when we leave this plane,
We will never meet again,
On the ever-branching paths of mitosis.
With centromeres in place,
We'll share a last embrace,
Then separate as anaphase is pending.
Our cell will split in two,
And we'll replicate anew;
A chromosome's travails are never-ending.
These roles we cannot quit;
We copy and we split
Until the cycle's finally subsiding.
In the end we'll understand
We were part of something grand:
All life on Earth is made of cells dividing!
• MP3 (demo with Monty Harper)
• 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. For example, certain aspects of the lyrics can be reinforced or enriched via kinesthetic movements. In the chorus of this song, consider possibilities such as the following:
- For "left road" and "right road," point left and right, respectively.
- For "mighty spindle pulls us," do a pulling motion, as if participating in a tug-of-war.
- For "when we leave this plane," extend one arm and hand, with your palm flat and the plane of your hand perpendicular to the ground. Move your hand up and down (somewhat like a gentle karate chop) to indicate the presence of an imaginary plane where the sister chromatids line up and then disperse from.
- For "ever-branching paths," spread your arms, hands, and fingers to represent the branching fates of cells produced by cell division.
Students can also be challenged to use the song (and any related knowledge that they have) to answer questions like those below.
(1) What is the definition of a chromatid?
(2) Do chromatids exist throughout mitosis?
(3) Are sister chromatids genetically identical to each other?
(4) What is meant by the phrase, "You'll take the left road, and I'll take the right road"?
(5) The lyrics say, "Our cell will split in two." Is this splitting of the cytoplasm part of mitosis?
(Answers may be found on the answers page.)