1. Someone doing manual labor what would you see when looking at a section of the dermis of their hands

1.
Someone doing manual labor what would you see when looking at a section of the dermis of their hands?
2.
A callus is a hardening of skin, which protein is very abundant here?
3.
What will happen if the sebaceous gland slows their function?
4.
Why does hair look shinier when we are sweating a lot?
5.
Skin grows from a particular layer, what is the name of this layer and what might happen if this layer gets damaged?