Integumentary System
Integumentary System
Includes skin, hair, nails, glands; also contains sensory receptors & vascular network
Skin
Functions of the skin
- Protection
- Thermoregulation
- Sensation:
- Tactile - touch and pressure
- Thermal - warmth and coolness
- Pain
- Excretion
- Water and some wastes
- Absorption
- Fat-soluble vitamins, O2, CO2, and some toxins - acetone, lead, mercury, and poison ivy, and oak
- Produces Vitamin D
2 distinct layers
- Epidermis
- Thinnest & outermost layer
- Composed of keratinized stratified squamous epithelium
- Dermis
- Deepest & innermost layer
- Composed of connective tissue
- Contains an abundance of blood vessels and nerve endings
- Hypodermis
- Also called the Subcutaneous layer
- Composed of Loose connective tissue & Adipose tissue
- Binds skin to underlying tissue
- If it is mostly adipose, it is subcutaneous fat
- Insulation and energy reservoir
^^Epidermis consists of 4 or 5 distinct layers dependent on location^^
- Stratum Basale - deepest
- Columnar stem cells
- Constantly reproducing pushing the older cells upward
- Stratum Granulosum
- 3-5 layers
- Keratinization begins
- Last layer with blood nutrient supply
- Stratum corneum
- Several cell layers thick (up to 30 layer)
- At the top is the flat dead layers which is composed of keratin
- Keratinocytes: new skin layers
- 4 Specialized cell types
- Keratinocytes - produce keratin (helps your hair and nails grow)
- Melanocytes - produce melanin (helps with pigmentation in hair and skin)
- Langerhans cells - associated with the immune system (produces good healthy immune system)
- Merkel Cells - touch receptors (in hands and all over the body - sends waves into the brain)
Temperature
- First impression
- Touch
- Measurement
- Celsius (0 and 100)
- Fahrenheit (32 and 212)
Normal Body temperature
Normal temperature is 98.6 degrees F (37 degrees C)
- Hyperthermia: increase in core temperature
- Temperature above 105℉ (41 degrees ℃): brain cells die, seizures
- Hypothermia: decrease in core temperature
- 93℉ (34℃): normal body warming fails
- 90℉ (32℃): shivering stops, heart sounds diminish, cardiac irritability increases
- 70℉ (21℃): Present with deathlike appearance and possible irreversible asystole
Places to take temperate
- Oral
- Rectal
- Axillary
- ear
Factors that affect temperature
- A person’s age and sex
- The time of day, typically being lowest in the early morning and highest in the late afternoon
- High or low activity levels
- Food and fluid intake
- For females, the stage in their monthly menstrual cycle
- The method of measurements, such as oral (mouth), rectal (bottom), or armpit readings
Formulas for conversion
Celsius to Fahrenheit: (Cx9/5)+32=F
Fahrenheit to Celsius: (F-32)x5/9=C
Abnormal Changes in Skin Color
| Condition | Skin Tone | Cause |
|---|---|---|
| Cyanosis | Blue tint | A deficiency of oxygen in circulating blood |
| Jaundice | Yellow discoloration of skin & the whites of eyes | Impaired liver function (hepatitis or liver disease) allows bile to accumulate, which stains the skin |
| Bronzing | A golden-brown skin color | A deficiency of hormones from the adrenal gland such as occurs with Addison disease |
| Albinism | Extremely pale skin, white hair, & pink eyes | A genetic lack of melanin |
| Erythema | Abnormal redness | Increased blood flow in dilated blood vessels close to the skin’s surface; may result from heat, exercise, sunburn, or emotions such as embarrassment or anger |
| Pallor | Pale skin | Decreased blood flow, such as occurs from cold temperatures, fear or emotional stress, low blood pressure, or blood loss |
| Bruise (Hematoma) | Bluish, black, or yellowish mark on the skin | The breakdown of clotted blood under the skin |
- Capillary Refill test (CRT)
- 2 seconds or less (CRT<2)
- 3 seconds or more (CRT>2)
\n