Theory 25/Hair follicle cycle/Onset phase
Anagen Starts on a Signal Ratio
The claim
A follicle enters growth above a threshold in the ratio of dermal papilla signal to inhibitory factor, so the same follicle cycles on a schedule set by that balance.
01Mechanism
Stem cell activation requires the activator to exceed the inhibitor; the ratio sets the timing.
02Prediction
Cycle timing should track the ratio.
03Refutation
Timing tracking follicle age would remove the balance.