The Integumentary System 2 Flashcards
Read the quick reviews
And get tested on those
Read the quick reviews
And get tested on those
Skin Appendages
are accessory organs that support the functions of the skin in maintaining body homeostasis.
• Hair and nails
• Cutaneous glands
Hair(pilus)
is a flexible strand of dead keratinized cells found over most skin surface made by hair follicles.
Functions
- Sense of touch
• Protect against sunlight and heat loss (scalp hair)
• Filter foreign particles (eyelashes and nasal hair)
Hair is produced
from the hair bulb of the hair follicle through keratinization.
• contains melanocytes to give hair colour
• contains hair follicle receptors to detect hair bending
• arrector pili muscle contracts to pull the hair follicle upright, pulls our hair when scared, stressed, cold
protects agginst heat loss
Hair root is embedded in the skin; hair shaft projects above the skin surface.
Look at diagram
Hair is classified as cells or terminal
Vellus: fine, short, and unpigmented hair.
• found on most thin skin
Terminal: long, coarse and darker hair.
• Grow in response to androgens (male-predominant sex hormones)
• E.g., eyebrow, eyelashes, scalp hair, pubic and axillary areas of both sexes
True or False:Vellus hair is the type of hair that becomes more prominent in androgenic hair loss, also known as male pattern baldness
True: In male pattern baldness, terminal hair become thinner and less pigmented due to hormonal imbalances.
In hirsutism, females develop terminal hair on the face and chest, a masculine distribution.
Nails
Are keratinized cells located over the dorsal surfaces at the ends of fingers and toes.
• produced by the nail matrix and rests on the nail bed
Nail functions
- fine manipulation grab things
• grooming and scratching
Dorsal side of nail
Top down
- free edge
- nail body
- lunula
- Eponychium
- Nail root
Which portion of the nail is embedded in the skin?
Nail root is embedded in the skin
• Nail body and free edge are visible portions of the nail
Why does most of the nail appear pink
Due to the rich blood vessels underneath
• Exception is the lunula (“little moon”), where the nail matrix is
Sebaceous(Oil) glands
Sebaceous glands are holocrine glands that secrete sebum (a mixture of oil and cell fragments).
Features:
• lubricate the hair and prevent skin dehydration
• has anti-bacterial property
• not found in thick skin
True or Galse: pimples, whiteheads, and blackheads are all problems associated with the sebaceous glands
Pimples may be associated with bacterial infection.
Whiteheads and blackheads result from sebum blockage of sebaceous gland duct.
Sudoriferous(Sweat glands)
Eccrine glands
are found all over the body, especially at the palms, soles and forehead.
• function in thermoregulation
- directly connected to the skin
Apocrine sweat glands
found in anogenital and axillary areas.
• secrete into hair follicles
• contribute to body odour when acted upon by bacteria
The composition of eccrine gland secretion is
99% water, salt, trace amounts of wastes and vitamin C
Specialized Apocrine Glands
Ceruminous glands
Produce cerumen(earwax) together with nearby oil glands
- found at the external ear canal
- insects and other things get tapped before going further down ear
Mammary glands
Secrete milk
- develops only during pregnancy and lactation
Linking each to the integ. system:
1. Physical barrier and protection
Keratin production
Linking each to the integ. system:
Regulation of body temp
Piloerection(goosebumps):
- through hair follicle receptors
Sweat(insensible+sensible):
- sweat pores
- eccrine sweat glands
Vasodilation and Vasoconstriction:
- dermal vascular plexus
Adipose tissue
Hi
Linking each to the integ system:
Blood reservoir
Vasodilation or vasoconstriction which stores up to 5% of the body’s blood volume through the dermal vascular plexus
- capillaries are smaller than arteries
Linking each to the integ system:
Sensation
- Merkel cells(pressure) through the epidermis
- Dermal Layer* Nociceptors (pain)
Subcolaneous, Meissner corpuscle (touch),
Pacinian corpuscle (vibration/pressure) and Ruffini’s corpuscle (stretch): - sensory nerve fibers with free nerve endings
- Lamilar corpuscle
Linking each to the integ system:
Excretion and absorption
Absorption through passive diffusion which the papillary and reticular layers of the dermis
Sweat: removal of water, salt and nitrogenous waste (eccrine), pheromones (apocrine) and sebum (oil) production though:
-• Eccrine sweat gland
-Arrector pili muscle
• Sebaceous (oil) gland
Linking each to the integ. system:
Vitamin D synthesis
UV-B stimulated production of vitamin D3 through the epidermis
Wearable medical devices
Are designed to be used while attached to the body
Questions to consider tor wearables
How long will the device remain on the patient?
• Where will the sensor be placed on the body?
• What skin types or conditions will be encountered?
• Will the skin require additional preparation?
• What is the demographic of the intended user? (infant, adult and/or elderly)
• What is the activity level of the user during use? (active or sedentary)
