The difference is primary happens naturally and the secondary responds to an disturbance.
<span>Since there's no choices attached on your questions on which of these is not a function of your skin. I'll give you one.
- Holds the bone of the skeletal system is not the function of the skin. Skin only protects.</span>
Carbon is the basis for all organic molecules. Silicone could also be the answer too though.
It would be the end of the day because it will be the answer