Normal Integumentary Flashcards
(33 cards)
List the 6 functions of the integumentary system
Barrier Immunologic Homeostasis Sensory Endocrine Excretion
Layers of epidermis from bottom to top
stratum basale stratum spinosum stratum granulosum stratum lucidium (only in thick skin) startum corneum
Epidermis has what type of cells?
Keratinized stratified squamous epithelial cells
Does the epidermis have a blood supply?
No- it is asvascular, but receives nutrients from the dermis
Stratum basale
- single row of keratinocytes
- has melanocytes and merkel cells
stratum spinosum
- melanin granules
- cells start to flatten
- Langerhans’ cells
Stratum granulosum
- 3-5 layers thick
- flattened, nuclei begin to disappear
- last level to get nourishment from dermis
stratum lucidium
- ONLY IN THICK SKIN
- flattened, dead keratinocytes
stratum corenum
- 75% of epidermal mass
- protect skin from penetration
- glycolipids waterproof this layer
Dermis- tissue type
Dense connective tissue
Function of dermis
- Mechanical support
- Strength
- Thickness to skin
- Vascular
Two layers of dermis
- Papillary layer
- Reticular layer
Papillary layers of dermis
- Loose connective tissue
- nipple like projection into epidermis (dermal papillae)
Reticular layer of dermis
- 80% of dermis
- dense, irregular connective tissue and collagen fibers
Hypodermis
- Subcutaneous fascia
- Variable amount of adipose tissue separated by connective tissue septa
Exoreceptors in the skin
- Free nerve endings
- Pacinian corpuscle
- Meissner’s corpuscle
- Ruffini corpuscle
Free nerve endings
end in stratum granulosum, fine touch, hair movement
Pancinian corpuscle
- Deep in dermis and hypodermis
- On finger tips
- Sense pressure and vibration
Meissner’s corpuscle
touch receptors and sensitive to low frequency stimuli in hairless skin of lips ant/post skin of hand and feet(fingers and toes)
Ruffini corpuscle
- Simple mechanoreceptor
- Respond to displacement of the connective tissue induced by sustained or continuous mechanical stress
Hair follicles
- Lined by epidermis that is continuous with surface
- smooth muscle is attached- Arrector Pili
Sebaceous gland
- Associated w/ hair follicles or empty directly onto skin
- Sebum keeps hair and skin soft and helps prevent water loss
Eccrine (merocrine) glands
- All over body
- Secretes sweat through pores directly onto body
- respond to temperature and emotions
- Under control of SNS
Apocrine glands
- Located in axillae, face, scalp, external genitalia
- empties sweat into hair follicles –> skin
