Amphibians have permeable skin that easily absorbs substances from the environment, and all frogs are amphibians. Given these facts, what feature allows frogs to absorb substances from the environment among the following options:
- four limbs
 - poison dart frog
 - hydrate their cells
 - permeable skin
 - layers of fat
 - a cuticle
 - predators
 - double eyelid


 

    permeable skin     