Skin Flashcards
What are the 3 layers of the skin?
- Epidermis
- Dermis
- Hypodermis
What is the hypodermis made up of?
- Adipose
- Loose connective Tissue
Name 3 functions of the hypodermis
- Energy store
- Insulation
- Shock absorber
- Connects skin to underlying muscles and bones
- Makes hormones to control hunger (leptin)
What is an alternative name for the dermis and what are its 3 layers?
- Corium
- Papillary
- Reticular
- Dermal Papillae
State 1 function of the dermis
- Contains hairs and sweat glands
- Sensory structures
- Gives structure to the skin
How many layers are in the epidermis and what cell proliferates it?
4-5 layers
- Keratinocytes
Name 2 functions of the epidermis
- Prevents water loss and bacteria entry
- Presents pathogens to immune cells
- Keratin synthesis
- Prevents tissue loss from abrasion
Name 2 of the 5 epidermal layers
- Stratum Corneum
- Stratum Lucidum
- Stratum Granulosam
- Stratum Spinosum
- Stratum Basale
What layer of the epidermis is not always present?
Stratum Lucidum
What does the Stratum Corneum contain and in which location is it thicker?
- Contains dead keratinocytes
- Thick on palms and soles
What epithelial cells are found in the epidermal layers?
- Stratified squamous
- Cuboidal epithelium
- Tall columnar epithelium
Which epidermal layer is the first with Golgi apparatus?
Stratum Spinosam
What assembles and secretes keratin fibrils?
Lamellar bodies
Which epidermal layer makes keratin filaments and has melanocytes?
Stratum Basale
Name 3 types of epidermal cells
- Keratinocytes
- Melanocytes
- Langerhans Cells
- Merkel Cells
Which epidermal cells are related to immune response?
Langerhans cells
What is the normal transit time of Keratinocytes?
28-40 days
What are Merkel Cells?
- Mechanoreceptor cells
- Associated with sensory nerve endings
What are the two types of skin?
- Hairy/Thin
- Non-Hairy/Thick
What does thin/hairy skin contain that thick/non-hairy skin does not?
- Hair follicles
- Sebaceous glands
- Arrector pili muscles
What are the 3 types of hair? Give a brief description of each
Lanugo - only present in embryo
Vellus - thin hair that replaces lanugo
Terminal - head/axillae/genital, stimulated by testosterone
What are the 4 functions of hair?
- Thermoregulation
- Sexual Attraction
- Sensation
- Protection
What muscle tissue makes up Arrector Pili Muscles and what are they attached to?
- Smooth muscle fibres
- Attached to dermis and hair bulb
Name 4 constituents of Mechanoreceptors
- End bulbs
- Free nerve endings
- Tactile discs
- Meissner Corpuscle
- Pacinian Corpuscle
- Ruffini’s Corpuscle
- Root Hair Plexus
What substance are nails made of?
Alpha keratin
Name 3 functions of nails
- Protection
- As a tool
- Enhances precise, delicate movements
- Enhances fingertip sensitivity
Describe 5 functions of the skin
- Protection and repair
- Temperature regulation
- Excretion of waste products
- Lubrication (sebaceous glands)
- Storage (Adipose tissue)
- Vitamin D synthesis
- Absorption
- Aesthetics
- Sensation
