Flashcards in Integumentry Ch 5 Deck (24)
Keratinized stratified squamous epithilium with 4 cell types and 5 layers
(4 in thin skin)
4 cell types
Dendrintic ( Langerhans cells)
Tactile (Merkel cells)
Produce keratin that gives epidermis its protective property. Most abundant epithelial cells.
Spider shaped, synthesize pigment melanin.
Langerhans cells, arise from bone marrow and migrate to epidermis. Ingest foreign substances and are key in immune defense.
Tactile, present at epidermal/dermal junction
Layers of the epidermis
Spinosum (prickly layer)
Lucidium (clear layer)
Cornuem (horny layer)
Layers of the Dermis
2nd major skin region
Papillary layer:Areolar connective tissue
Reticular layer:Dense fibrous connective tissue
Cleave tension lines
separations or less dense regions
Skin markings, dermal folds that occur near joints
Skin color pigments:
Melanin, Carotene and Hemoglobin.
Hard kerotinized cells, do not flake off, strong and durable.
3 concentric layers of hair
Medulla: central core, soft keratin (matrix below produces hair)
Cortex: bulky, hard, layer surrounding the medulla
Cuticle : outermost
2 types of hair
Vellua: pale, fine, body hair
Terminal:coarse long hair of eyebrows and scalp
2 types of glands
Sudoriferous (Sweat Glands)
Sudoriferous - Sweat Glands
Merocrine: secrete sweat
Apocrine: secrete sweat + protein
Secrete products in hair follicles
Axilla, nipples, pubic region
Begin at puberty
Controlled by nervous system and hormones
Secrete oil called sebum, kills bacteria on skin, lubricates and protects keratin, and conditions skin.
Sebaceous follicles are not associated with hair follicles, discharge onto the epidermis.
Chemical barriers: Acid mantle
Biological barries: dendritic cells, macrophages and DNA
Basal cell: most common least malignant
Squamous cell: 2nd most common, affects keratinocytes
Melanoma: least common most dangerous
Accessory structures of the integument:
The portion of the hair follicles where cell division occurs s the
Regeneration of injured skin:
1) Inflammation: bleeding and regeneration
2) Migratory phase: scab and granulation tissue formation
3) Proliferation phase: loss of granulation and undermining of the scab
4) Scarring phase