Definition: A unit for expressing the relative distance between genes on a chromosome.

Alright class, settle down now, let’s dive in with a bow! Today we’re tackling a term, quite precise and neat, Called “Morgan,” a measurement, oh so sweet! Now you read that dictionary line, it's true, "A unit for expressing distance, between genes anew." But what does "Morgan" really mean, you see? It’s about how genes are spaced, for you and me! Think of a chromosome, long and grand, With genes arranged like jewels in a planned strand. One Morgan is roughly three million base pairs wide, A distance that scientists carefully guide. It's named after Thomas H. Morgan, clever and bright, Who used this unit to study with all his might! He worked with fruit flies, a fascinating quest, To map the genes and put them to the test. So remember this lesson, clear and strong, "Morgan" is distance – where genes belong! Do you have any questions? Let's discuss with glee, Now who can tell me, what a Morgan might be?