Having developed an amateur interest in cell biology over the last few years, the single most interesting thing I've learned is that Interglobulin-M cells cells just happen to have same basic morphology as the kind of animals that they come from.

I have no idea what that means, but I'm curious to know. Can you point to anything I could read?

I'm so sorry, I should have written immunoglobulin-M and didn't notice my mistake. I don't feel qualified to recommend a text, I just follow references from here.

https://en.wikipedia.org/wiki/Immunoglobulin_M

Thanks. :) That's what I found when I searched, but the spelling difference threw me off.

You can watch acapellascience answer this question to the tune of 'Despacito'!

https://youtu.be/ydqReeTV_vk

That explains what the central dogma is, but not how specific patterns of gene expression lead to a horse. That's something that's still quite a mystery. Hell, even after a lot of work, we don't still entirely know how even something as simple as Drosophila does its segmentation.