From SN 22.79, Sankhara is :
Sankhara produce conditioned phenomena; that’s why they’re called ‘Sankhara’. Saṅkhatamabhisaṅkharontīti kho, bhikkhave, tasmā ‘saṅkhārā’ti vuccati.
And what are the conditioned phenomena that they produce?
Kiñca saṅkhatamabhisaṅkharonti?
Form is a conditioned phenomenon; choices are what make it into form. Feeling is a conditioned phenomenon; choices are what make it into feeling. Perception is a conditioned phenomenon; choices are what make it into perception. Choices are conditioned phenomena; choices are what make them into choices. Consciousness is a conditioned phenomenon; choices are what make it into consciousness.
In Phenapandima Sutta SN 22.95
Suppose there was a person in need of heartwood. Wandering in search of heartwood, they’d take a sharp axe and enter a forest. There they’d see a big banana tree, straight and young and grown free of defects. They’d cut it down at the base, cut off the top, and unroll the coiled sheaths. But they wouldn’t even find sapwood, much less heartwood. And a person with clear eyes would see it and contemplate it, examining it carefully. And it would appear to them as completely void, hollow, and insubstantial. For what substance could there be in a banana tree?
In the same way, a mendicant sees and contemplates any kind of choices at all … examining them carefully. And they appear to them as completely void, hollow, and insubstantial. For what substance could there be in choices?
So can sankhara be understood as following?
Perception as a conditioned phenomena
“This is a tree” → Perception
What is a tree?
“Tree is something with leaves” → Perception
What are leaves?
“Leaves are green” → Perception
What is green?
"Green is a color " → Perception
What is a color?
“Color is a specific sensation from eyes” → Perception
…
Form as a conditioned phenomena
Form is made of matter → Matter is made of molecules → Molecules made of elements → Elements made of Atoms → Atoms made of electrons, neutrons → Quarks → Quantum Fields theory → String theory → etc. …
This seems to be layered endlessly and only end I can think is assuming " I don’t know". It seems this is similar to the banana tree analogy.
Is this the correct approach to contemplate? or is there a different way?