01 - Structure and Function of the Skin Flashcards
(General Function of the Skin)
(Barrier)
(physical)
- prevention of water, electrolyte and macromolecule loss
- prevent invasion by external agents (chemical, physical, microbial)
- what constitutues the physical barrier?
- stratum corneum
(General Function of the Skin)
(Barrier)
(Physiologic)
- Turnover rate: what is the turnover time for a keratinocyte to pass from basal layer to surface? Injuries affect mitotic rate how?
- sebum: the fatty acids perform what two functions?
- 30 to 45 days; increase (shorter time for keratinocytes to reach surface)
- bacteriostatic and fungistatic
(General Function of the Skin)
(Barrier)
(Immunologic)
- Keratinocytes, langerhan’s cells, and lymphocytes provide immunosurveillance capacity that effectively protects againt development of what?
- cutaneous neoplasms and persistent infections
(General Function of the Skin)
(Barrier)
(Microbial Flora)
- normal bacteria flora do what?
- fungal and viral phyla also participate also serve same function
- inhibit growth of pathogens
(General Function of the Skin)
(communcation)
- sensory: primary sense organ for touch, pressure, pain, itch, heat, and cold
- immunologic: langerhan’s cells present antigen to what where?
- lymphocytes in regional lymph nodes
(General Function of the Skin)
(Temperature Regulation)
- hair coat
- cutaneous blood supply
- subcutaneous fat
- sweat gland function
horses. .. what kind of sweat?
dogs and cat… what kind of sweat where?
- apocrine sweat
eccrine sweat in footpads only
(General Function of the Skin)
(secretion)
- what three gland types?
1.apocrine, eccrine, and sebaceous
(General Function of the Skin)
(Storage)
- reservoir of electrolytes, water, vitamins, fat, carbohydrates, proteins, and other materials
(General Function of the Skin)
(Pigmentation)
- what three things determine the color of skin and coat?
- pigmentation of skin helps protect from what?
- what is produced in skin by stimulation by solar radiation?
- melanin formation, vascularization, keratinization
- solar radiation damage
- vitamin D
(General Function of the Skin)
(Adnexa Production)
- skin produces keratinized structures such as hairs, nails, claws, hooves, and the horny layer of the epidermis
(General Function of the Skin)
(indicator)
- of general health and disesase
(General Function of the Skin)
(Motion and Shape)
- flexibiilty, elasticity, and toughness of the skin allow motion and provide shape and form
- many species differences
(Overview of the Skin Structure)
(Regions of the Skin)
1-5. name the five regions
- epidermis
- dermal-epidermal junction
- dermis
- hypodermis (subcutaneous tissue)
- epidermally derived appendages (hair follicles, sebaceous glands, apocrine sweat glands, eccrine sweat glands, nails/claws/hooves)
(Structure of the Epidermis)
1-5. What are the five layers of the epidermis?
- basal layer (stratum basale or stratum granulosum)
- spinous layer (stratrum spinosum)
- granular layer (stratum granulosum)
- clear layer (stratum lucidum)
- horny layer (stratum corneum)
(layers of the epidermis)
(basal layer: stratum basale or stratum germinativum)
- one layer of cubodal to columnar cells called what and what?
- keratinocytes account for what percent of cells? melanocytes? merkel cells?
- basal layer is the site of what?
- cell-to-cell attachments are characterized mainly by what (between keratinocytes)?
- keratinocytes and melanocytes
- 90%; 10%; < 1%
- cell division (mitosis)
- desmosomes
(dynamic. .. allow movement between and movement of cells upward)