System that contains hair, skin, and oils. It covers the whole body, is 7% of weight, and is very thin.
2. Describe and give at least one example of each of the functions of the integumentary system.
Protection- different barriers to keep pathogens out. Ex- sebum
Body temperature regulation- helps with homeostasis. Ex- production of sweat
Sensory- receptors in the skin detect different things. Ex- nerve endings detect pain
Metabolic function- chemical conversions and production of vitamins. Ex- vitamin D
Blood reservoir- constriction and dilation of blood vessels. Ex-blood vessels
Excretion- elimination of different substances. Ex- salt and water
3. Differentiate between chemical, physical/mechanical and biological barriers provided by the integumentary system. Be sure to provide a minimum of one example for each.
Chemical Barriers (skin secretion and melanin)
Physical/Mechanical Barriers – continuity of the skin and hardness of keratinized cells Biological Barriers – Langerhans’ cells, macrophages, and DNA
4. Create a chart that helps you differentiate the epidermis and dermis. Be sure to include things such as cell composition, cell populations and layers.
A. Epidermis
Composed of epithelial tissue (keratinized stratified squamous)
Cell population:
-Keratinocytes (majority) – produce keratin
-Melanocytes – synthesize melanin .
-Langerhans’ cells (aka epidermal dendritic cells) – macrophages
- Merkel cells – sensory reception
Subdivided into four or five distinct layers
- Stratum basale (aka, stratum germinativum) – deepest layer
-Stratum spinosum
-Stratum granulosum
-Stratum lucidum (thick skin only)
-Stratum corneum – outermost layer
B. Dermis
Composed of fibrous connective tissue
Cell populations
- Fibroblasts producing a semi-fluid
5. Order the layers of the epidermis from outermost to deepest.
STRATUM CORNEUM
STRATUM LUCIDUM
STRATUM GRANULOSUM
STRATUM