Final answer:
The skin's major function is temperature regulation through sweat production, as well as serving as a protective barrier and blocking UV light.
Step-by-step explanation:
One of the major functions of the skin is temperature regulation. When the body is too warm, the skin produces sweat, which cools the body when it evaporates. The skin also acts as a protective barrier, preventing water loss from the body and serving as a barrier to the entry of microorganisms. Additionally, melanin in the skin blocks UV light and protects deeper layers from its damaging effects.