BIO 235 AP I
Chapter 6- Skin and the Integumentary System 1. Define the following word parts. cut- skin kerat- horn derm- skin melan- black epi- upon, after, in addition seb- grease follic- small bag 2. List the general functions of the skin? It is a protective covering, retards water loss, helps regulate body temperature, houses sensory receptors, synthesizes various chemicals and excretes small quantities of waste.
3. Name the tissues found in the outer layer of skin, inner layer of skin and subcutaneous layer (beneath the skin). The outer layer is the epidermis layer of skin; it is composed of stratified squamous epithelium. The inner layer or dermis layer is made up of connective tissue containing collagen and elastic fibers, smooth muscle tissue, nervous tissue, and blood. The subcutaneous layer is made up of areolar and adipose tissue also the collagenous and elastic fibers of this layer are continuous with those of the dermis.
4. What are the functions of the subcutaneous layer? The subcutaneous layer contains adipose tissue that acts as an insulator, helping to conserve body heat and preventing the entrance of heat from the outside. It also contains the major blood vessels that supply the skin.
5. Explain how the epidermis if formed. The cells of the epidermis divide and grow; the older cells of this layer are pushed away from the dermis toward the skin surface forming the epidermis.
6. List the protective functions of the epidermis. It shields the moist underlying tissues against excess water loss, mechanical injury, and the effects of harmful chemicals; when intact it also keeps out disease-causing micro-organisms.
7. Describe each of the following layers of the epidermis:
Stratum corneum- Outermost layer; many layers of keratinized, dead epithelial cells that are flattened and nonnucleated.
Stratum lucidum- Between stratum corneum and stratum granulosum on soles and palms;