Whenever school gets you down, Master Brown
And science seems hard, or tough
Biology's difficult, obtuse or daft
And you feel that you've had quite enough...

Just remember that you're living in a body that's inspiring
And respiring with ten million million cells
Each one is point-oh-five millimetres side to side
And full of lots of types and kinds of organelles
The nucleus is small - 100 nanometres tall
We make millions of new ones every day
And our chromosomes, it seems, contain 100,000 genes
In a double-stranded helix DNA

Our genome itself contains three billion base pairs
Each one GC or AT side by side
But just one-sixty millions, of those 3.2 billions
Are actually encoding nucleotides
To make one whole protein, it takes but a single gene
Say, fifteen hundred nucleotide pairs
And the whole genetic sequence has millions of billions
Of permutations for our varied life on earth

Our cells and DNA keep on dividing and dividing
Mitosis makes a carbon-copy cell
But so we can reproduce, some cells they will produce
Meiotic'ly a haploid one as well
Two haploids can combine, say, one of yours and one of mine
To create uniquely sequenced DNA
And with this replication comes occasional mutation, so
Evolution comes about this way