Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
|
What are the functions of the integumentary system? |
Protection, Sensations, Thermoregulation, Evaporation/Resistance, Storage, Synthesis, Excretion, Absorption
|
|
|
What are the three structural layers of the integumentary system?
|
Epidermin, Dermis, Subcutis/hypodermis
|
|
|
What is the epidermis?
|
External layer No blood vessels Stratified squamous epithelium Mixed cell types Five layers Constant state of replenishment |
|
|
What are the cell types?
|
Keratinocytes - ~90% of total, produce keratin, crosslink/harden forming protective cornified layer. Melanocytes - ~10% of total, produce melanin, pigmentation cells. Langerhans cells - dendritic cells, immune function. Merkel cells - rare mechanoreceptors, sensation. |
|
|
What are the five layers?
|
Stratum corneum (horny layer) Stratum lucidum (only in thick skin - feet) Stratum granulosum (modifying layer) Stratum spinosum (prickly layer) Stratum basale (mitotic layer - sloughing off) |
|
|
Why is there a constrant rate of replenishment?
|
Migration from inner mitotic basale layer. Replace dying/damaged cells |
|
|
Tell me about the Dermis.
|
Under basement membrane. Strong with high collagen content forstructure stability. Flexible with elastin allowing stretch. Dermis forms bulk of skin mass. |
|
|
Describe the structure of the dermis under the basement membrane.
|
Thin fiberous sheet underlying epithelial layers. Anchors to dermis via cell-matrix adhesions. Mechanical barrier to invaders. |
|
|
What are the two layers of the dermis?
|
Papilary layer and reticular layer.
|
|
|
Describe the papilary layer.
|
Thin outer layer. Connective tissue. Blood vessels/lymph vessels. Dermal papillae - outjuts into epithelial layer, capillary beds for nutrient supply, structural basis for finger prints. |
|
|
Describe the reticular layer.
|
Thick inner layer, loose irregular connective tissue. Collagen - strength and resilience. Elastic - stretch recoil. Proteoglycans - hydration/viscosity. Pigments for tattoos. |
|
|
What are the cells found in the derms?
|
Fibroblasts, macrophages, mast cells, nervous fibers/sensory receptors, myocytes, hair follicles, sweat glands, sebaceous (oil) glands, apocrine (secreting) glands - milk glands. |
|
|
Describe the subcutis/hypodermis
|
Under dermis. Loose connective tissue/fat - major repository of fat/adipose tissue, energy reservoir. Funcion - anchor between skin and underlying structures, route for vessels to/from skin, nerves, some glands, panniculus carnosus - superficial thin muscle layer - scalp, testes, nipple, palm, face. |
|
|
How does skin dysfunction/damage occur?
|
Disruption in self renewal. Destruction/penetration of skin. Failure of epidermal strength. |
|
|
What does skin dysfunction/damage result in?
|
Mechanical stress/tears. Lack of biological homeostasis. Defective immunological function. |
|
|
How are skin lesions classified?
|
Lesion type (primary morphology). Lesion configuration (secondary morphology). Texture. Distribution. Color. |
|
|
What are the differences in primary lesions?
|
Size, morphology, layers impacted
|
|
|
What are the types of primary lesions?
|
Macule, patch, papule, nodule, plaque, vesicle, bulla, pustule, cyst, wheal, burrow, ulcer
|
|
|
Describe a macule.
|
<0.5cm. Different colour: brown - melanin, red - vasodilation. With or without inflammation. Flush with skin - can see but not touch. Freckles. Defined edges - mostly epidermal. Indistinct margins - larger dermal component |
|
|
Describe a patch.
|
>0.5cm Birth mark. Defined edges - mostly epidermal. Indistinct margins - larger dermal component |
|
|
Describe a papule.
|
<1cm. Solid. Raised. Distinct borders. May have crust or scales. Range of morphologies - caused by physical damage by disease, domed, flat-topped, umbilicated. Acne, hypersensitivity reactions, fungal infections. |
|
|
Describe a nodule.
|
>1cm. Raised above surface of skin. Solid round or oval lesion. Origin in epidermis, dermis or subcutaneous. Basal cell carcinoma. Lipoma - adipose deposit. Rhuematoid arthritis. |
|
|
Describe a plaque/plateau.
|
Raised above surface of skin. Flat topped lesion. Edges can be distinct or variable. Psoriasis. Eczema. |
|
|
Describe a vesicle.
|
<0.5cm. Fluid filled. Raised above skin. Translucent. Blisters |
|
|
Describe a bulla.
|
>0.5cm. Blisters |
|
|
Describe a pustule.
|
Pus filled. Raised above skin. Tend to be infected - acne, folliculitis. Can be sterile - pustular psoriasis. |
|
|
Describe a cyst.
|
Closed cavity. Liquid/semi solid material. Abscess - filled with pus. |
|
|
What is wheal?
|
Transient, raised, red, edema, upper epidermis.
|
|
|
What is a burrow?
|
Linear lesion. Infestation/tunneling in skin. Scabies. |
|
|
What is an ulcer?
|
Destruction, damage, removal of tissue, epidermis and/or dermis |
|
|
How does a secondary skin infection occur?
|
Can evolve from primary lesion. Introduced by external source - scratch, trauma, infection, or healing |
