What is the INTEGUMENTARY SYSTEM composed of?
- mammary glands
What are the functions of the EPIDERMIS?
- protect dermis form trauma
- control skin permeability
- prevent entry of pathogens
- synthesize vitamin D
- sensory receptors to detect touch, pressure, pain, and temp
- coordinates immune system response
What are the layers of the DERMIS?
papillary layer and recticular layer
What are the functions of the PAPILLARY LAYER of the dermis?
nourish and support the epidermis
What are the functions of the RECTICTULAR LAYER of the dermis?
- restricts spread of pathgens
- stores lipids
- attaches skin to deeper tissues
- blood vessels to assist in thermoregulation
What do the SENSORY RECEPTORS of the RECTICULAR LAYER detect?
What are the functions of HAIR FOLLILES?
- produce hairs that protect skull
- produce hair that provide delicate touch sensations
What are the functions of EXOCRINE GLANDS?
- assist in thermoregulation
- excrete waste
- lubricate epidermis
What are the functions of the INTEGUMENTARY SYSTEM?
- physical protection
- reguklation of body temp
- excretion/ secretion
- nutrition synthesis
- immune defense
What is the SKIN and its layers?
- cutaneous membrane
- epidermis and dermis
Describe the EPIDERMIS.
- stratified squamous
- *does not have blood vessels
- **relys on dermis
- underlying LCT
- *has blodd vessels
What are KERATINOCYTES?
- skin cells
- produce keratin
What are MELANOCYTES? where are they found? function?
- pigment cells
- protect from UV radiation
- deep in epidermis
What are MERKEL CELLS?
What are LANGERHANS CELLS?
What are the EPIDERMAL LAYERS from deep to most superficial?
- stratum basale
- stratum spinosum
- stratum granulosum
- stratum lucidum
- stratum corneum
Characteristics of the STRATUM BASALE
- basal layer
- attached to basal lamina
- has epidermal stem cells
- and merkel cells
Characteristics of the STRATUM SPINOSUM.
- keratinocytes bound together by maculae
- langerhans cells and melanocytes
Characteristics of the STRATUM GRANULOSUM.
- 1-2 layers thick
- keratin fibers develop as cells become thinner
- cells membrane thickens
- organelles disintegrate
- cells die
Characteristics of the STRATUM LUCIDUM.
- 1 cells thick
- appears as glassy layer in thick skin
- no nucleus
Characteristics of the STRATUM CORNEUM.
- multiple layers of flat, dead interlocking keratinocytes
- water resistant but not water proof
- permits slow water loss
What is HAIR?
- extends beyond surface of skin
- 98% NOT on head
What are HAIR FOLLICLES?
organs that form hairs, alive
Functions of SEBACEOUS GLANDS.
- secrete oily lipids that coat hair shaft and epidermis
- provide lubrication and antibacterial action
Functions of SWEAT GLANDS.
- produce watery solution by merocrine secretion
- flush epidermal surface
Types of SEBACEOUS GLANDS and how they secrete.
- Typical (secrete into hair follicles)
- Sebeceous Follicles (secrete onto skin surface)
Types of SWEAT GALNDS.
- Apocrine aka ODORIFEROUS
Describe ODORIFEROUS (apocrine) SWEAT GLANDS.
- limited distribution (axillae, groin, nipples)
- produce secretion of complex composition
- strongly influenced by hormones
Describe MEROCRINE SWEAT GLANDS.
- produce thin secretions, mostly water
- merocrine secretion mechanism
- contolled by nervous system
- role in thermoregulation and excretion
What is ACELLULAR SCAR TISSUE the result of?
the inability to completely heal after severe damage