Here's the TF stages and the various things I found based on several of my playthroughs:
Stage 0: Long, velociraptor-like nails. Your nails are exposed to the public. You must buy gloves from the vending machine to decrease exposure.
Stage 1: Raptor snout. Your snout is exposed to the public. You must buy a face mask from the vending machine to decrease exposure.
Stage 2: Short tail.
Stage 3: Reptilian feet.
Stage 4: Raptor eyes. Your eyes are exposed to the public. You must buy safety googles from the vending machine to reduce exposure. You can now go directly to the Specimen Containment Wing. If you are already there, you can go directly to the living quarters.
Stage 5: Raptor claws. If you are wearing gloves, they will tear apart and become useless.
Stage 6: Raptor feet. Clawed feet is now exposed.
Stage 7: Long tail. Your tail is now exposed. You must buy a lab coat to partially hide it.
Stage 8: Raptor face. You are practically an anthro raptor. Your face mask is no longer useful.
Stage 9: Digitigrade. You now look like the raptors from the "Jurassic Park" franchise. You must buy a lab coat to cover it up partially.
Stage 10: Feathers along your body. You can still play the game, but you can't really do much at this point unless your exposure level's not at 100%. If you are in the genetics lab and have already found a DNA stabilizer to try and cure yourself, you will unlock one of the game's endings.