One of them is its use as a selective physical barrier against foreign pathogens and harmful chemicals. At this level it serves as part of the nonspecific immune system in humans.
[header] How to study the structure and function of human skin [title] Learn about the histology of skin in humans. [step] The skin of humans is composed of several histologic layers that are different than other creatures in the animal kingdom. This histologic structure is important for various reasons.