epidermis The outermost layer of the skin; forms the waterproof, protective wrap over the
body’s surface; made up of many layers of epithelial cells.
integumentary system The outer covering of the body; made up of the skin, hair, and
nails.
keratin Tough, waterproof protein that is found in epidermal skin cells, nail, and hair.
melanin The brownish pigment that gives skin and hair their color.
melanocyte Melanin-producing cells; found in the bottom layer of the epidermis.
melanoma Cancer of melanin-containing cells (melanocytes); mostly linked to long-term
exposure to UV radiation.
oil gland Skin organ that secretes an oily substance, called sebum, into the hair follicle.
subcutaneous tissue Fatty layer of tissue that lies under the dermis, but is not part of
the skin.
sunburn A burn to the skin that is caused by overexposure to UV radiation from the sun’s
rays or tanning beds.
sweat gland Gland that opens to the skin surface through skin pores; found all over the
body; secretes sweat.
Points to Consider
- How might what you eat affect your bones?
- What do you think is the most important function of your skeletal system?
16.3 Lesson 16.3: Skeletal System
Lesson Objectives
- Identify the main tissues and organs of the skeletal system.
- List four functions of the skeletal system.
- Describe three movable joints.
- Identify two nutrients that are important for a healthy skeletal system.
- Describe two skeletal system injuries.