Describe the structure of the layers of the skin (pp.178-184)

The skin is the largest organ of the body, area of about 20 square feet
The skin protects us from microbes and the elements, helps regulate body temperature, and permits the sensations of touch heat and cold.

Well, both latitude and intensity of light affect temperature because, the higher the light intensity, the higher the temperature and since latitude is the measure of how close you are to the equator, then the closer to the equator you are, the higher the temperature is.