3. The skin and its parts (sweat & oil glands, hair, and nails) make up a complex set of organs, forming the integumentary system .
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5. The skin has several types of sensory receptors that allow sensations like… Pressure Heat Cold Pain
6. The integument (Latin, “ covering ”) accounts for ~7% of body weight.
7. Skin varies in thickness from 1.5 – 4.0 (or more) millimeters thick.
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9. Just under the skin is the hypodermis , or superficial fascia. It isn’t part of the skin, but it shares some of its function. It consists of adipose and areolar connective tissue, and it serves as a shock absorber and an insulator.
10.
11. Epidermis The epidermis is a keratinized stratified squamous epithelium, consisting of 4 distinct cell types and 4-5 distinct layers.
55. Hair and Hair Follicles The main function of body hair is to sense insects. The hair on the scalp guards against head trauma, heat loss, and sunlight. Eyelashes shield eyes and nose hairs filter the air.