Week 1: Skin Anatomy Flashcards
How thick is the skin typically?
0.5-6mm (depending on area of body)
The skin receives _____ of the resting cardiac output.
1/3 (more if damaged)
How thick is the epidermis?
0.06-0.6 mm
Is the epidermis vascular or avascular?
avascular
How long does it take for cells to move from basale (germinativum) to the corneal layer?
14-21 days
What does the basement membrane do?
attaches the dermis to the epidermis
What are the layers of the epidermis (top-down)?
Stratum Corneum Stratum Lucidum Stratum Granulosum Stratum Spinosum Stratum Germinativum (Basale)
What are the different epidermal cell types?
Keratinocytes
Melanocytes
Merkel Cells
Langerhans Cells
Which cells are the tougher outer layer of the skin?
Keratinocytes
Which cells give skin their pigment and are located close to the basement membrane?
Melanocytes
Which cells are a type of mechanoreceptor and are anchored to the keratinocytes?
Merkel Cells
Which cells are the first line of defense in the epidermis?
Langerhans Cells
What are the epidermal appendages?
Hair
Sebaceous Glands
Sudoriferous Glands
Nails
What is the acid-base mantle?
skin has an acid-base mantle (a mixture of sweat and sebum that produces a 4-5.5 on the pH scale)
What are the 3 places on the body that that don’t have epidermal appendages?
Lips, ears, nails
What are the functions of the epidermis?
- Provides a physical and chemical barrier
- Regulates fluid
- Provides light touch sensation
- Assists with thermoregulation
- Assists with excretion
- Critical to endogenous vitamin D production
- Contributes to cosmesis/appearance
What are the dermal layers? (top-down)
Papillary dermis
Reticular dermis
How thick is the dermis?
2.0-4.0 mm
Is the dermis vascular or avascular?
Highly vascular
What is the dense, irregularly arranged connective tissue layer that provides structural support?
Reticular dermis
What else does the dermis contain?
superficial lymphatics, nerves and superficial nerve endings, extracellular matrix
What are the dermal cell types?
Fibroblasts
Macrophages and White Blood Cells
Mast Cells
What do mast cells do?
histamine
What are the functions of the dermis?
- Supports and nourishes epidermis
- Houses epidermal appendages
- Assists with infection control
- Assists with thermoregulation
- Provides sensation
What are the different aspects of the subcutaneous tissue (hypodermis)?
Adipose tissue
Fascia
Deeper tissues: muscles, tendons, ligaments, joint capsules, bone
What are the functions of the adipose tissue?
Energy
Cushion
Insulation
Stores fat soluble vitamins (ADEK) and deeper lymphatic vessel
What is fascia?
fibrous connective tissue that separates and surrounds structures (structural maintenance component)
What is involved in superficial wounds?
epidermis only
What is involved in partial-thickness wounds?
epidermis and part of dermis (will feel pain, pressure)
What is involved in full-thickness wounds?
epidermis, dermis, into subcutaneous (possible muscle and/or bone)
What are examples of superficial wounds?
abrasion, first-degree burn
What are example of partial thickness wounds of the epidermis?
blister
What are examples of partial thickness wounds of the dermis?
Second-degree burn, stage II pressure ulcer, Wagner grade I ulcer
What are examples of full thickness wounds of the epidermis?
third-degree burns
What are examples of full-thickness wounds of the dermis?
fourth-degree burns
What are examples of full thickness wounds of the subcutaneous tissue?
stage III pressure
What are examples of full thickness wounds of the deeper tissues?
Wagner grade 2-5 ulcer
