05/11/2023 Notes Flashcards
What are some differences between thick and thin skin?
Thick skin contains all 5 layers of the epidermis, but have no hair follicles or sebaceous glands. Thin skin only have 4/5 layers of the epidermis and contain hair follicles and sebaceous glands.
What are sebaceous glands?
Oil glands found on the skin
What layer of the epidermis is missing in thin skin?
Stratum Lucidum
What three pigments contribute to skin color?
Melanin, hemoglobin, carotene
Melanocytes synthesize what?
Melanin
What shades does melanin give to the skin?
Yellow, red, brown, and black
Where is hemoglobin found?
In red blood cells within dermal blood vessels
What creates a reddish/pink color in the skin?
Hemoglobin
What foods give skin carotene?
Squash, corn, carrots
Carotene turns the skin into what color?
Yellow-orange
What is carotene converted into?
Vitamin A
Where does carotene accumulate?
Keratinocytes of stratum corneum and subcutaneous fat
What are some examples of abnormalities in skin color? (7)
Albinism, vitiligo, cyanosis, acrocyanosis, pallor, jaundice, erythema
What is caused by little to no production of melanin in the skin that results in a pale skin color over the entire body?
Albinism
What is vitiligo?
A skin discoloration caused by lack of melanin on the skin, resulting in patches of lighter skin color
What does cyanosis signify?
Poor blood oxygenation
Where is acrocyanosis typically found?
In the extremities (fingers and toes)
What is deoxyhemoglobin?
Poorly oxygenated hemoglobin that has a bluish tint
What skin discoloration is signified by lack of hemoglobin or red blood cells, paleness, or anemia?
Pallor
What is jaundice caused by?
Excess bilirubin
What is a breakdown product of hemoglobin?
Bilirubin
What can jaundice signify?
Liver damage from alcoholism
What is redness of the skin?
Erythema
What is another name for Livor Mortis?
Postmortem Lividity
What is postmortem lividity used for?
Used in identifying a time of death; blanching occurs 1-2 hours after death and stops after 8 hours
What are four types of skin markings?
Moles, freckles, hemangioma, and epidermal skin ridges
What is a nevus caused by?
Moles are caused by excessive melanocytes
What is melanoma?
Most dangerous form of skin cancer
What is caused by overactive melanocytes that produces lots of melanin?
Freckles
What is a congenital abnormality that results in skin discoloration from blood vessels that proliferate and tend to become a birthmark for life?
Hemangioma
What are some examples of hemangioma?
Port-wine stain, salmon patches, strawberry hemangioma
What creates epidermal skin ridges, or fingerprints?
Large folds and valleys of both dermal and epidermal tissue
Where are epidermal skin ridges found?
Fingers, palms, toes, soles
Do people have identical epidermal skin ridges?
No, the majority of people have unique epidermal skin ridges
What is found deep to the epidermis and superficial to the hypodermis?
Dermis
Blood vessels in the dermis nourish what structures?
Living portion of the epidermis and numerous supporting components of skin
The dermis contains lots of what? (5)
Collagen, elastic fibers, blood vessels, nerves, and epithelial glands
What are the two layers of the dermis?
Stratum Papillarosum (papillary layer) and Stratum Reticularosum (reticular layer)
The stratum papillarosum contains lots of what?
Nerve endings
Epidermal ridges and dermal papillae found in the papillary layer do what?
Increase area of contact between the dermis and epidermis
The stratum reticularosum contains lots of what?
Collagen and elastic fibers that contribute to the skin’s strength and elasticity
What are some other names for stretch marks?
Lineae Albicantes or Striae
How are stretch marks formed?
Rapid stretching of reticular layer of dermis which tears collagen fibers
What causes skin wrinkling and sagging?
Aging, reduced elasticity of skin, and excessive exposure to UV light
What are Lines of Cleavage (tension lines)?
Linear orientation of the skin formed by collagen and elastic fibers
What significance to lines of cleavage hold in surgery?
Parallel cuts to lines of cleavage promotes healing, reduces scarring, and suturing becomes easier
What is the common name for Decubitus Ulcers?
Bed sores
How are bed sores formed?
Continuous pressure on a body part that reduces blood flow and results in cell death
What are common locations for decubitus ulcers?
Sacrum, ischial tuberosities, and greater trochanter
How are bed sores prevented in patients that are unable to move themselves?
By moving them around every two hours
Is the hypodermis considered part of the integument?
No, but the hypodermis is closed associated with the integument
What can be found in the hypodermis?
Adipose tissue (fat), blood vessels, and loose fibrous connective tissue
Why is the hypodermis a good target for subcutaneous therapeutic drug injections?
The hypodermis has a good blood supply
Where is the majority of fat (adipose tissue) found?
In the hypodermis
What is liposuction?
A highly invasive procedure that sucks out fat
Where are nails found?
On the distal dorsum of digits
What are the functions of nails?
Protect the digits and aids in grasping small objects
What do hardened, transparent stratum corneum form?
Nails
Why do toenails grow slower than fingernails?
Toenails have less blood supply than fingernails
