Integumentary System Flashcards
Cutaneous layer
Skin
Integument
Skin
Integumentary system consists of:
Skin, nails, hair, skin glands
Homeostasis
Internal environmental balance
Dermatology
Scientific study and treatment of the Integumentary system
Integument tissues:
Epithelial tissue, connective tissue, vascular tissue, nervous tissue
Distinct layers of integument:
Epidermis, dermis (hypodermis is not actually apart of Integumentary system)
Deep to the dermis is what layer
Hypodermis or subcutaneous layer
Small population of immune cells in skin
Epidermal dendritic cells
Vasoconstriction
Blood vessels constricting
Vasodilation
Blood vessels dilate
Functions of integument
Protection, prevention of water loss, temperature regulation, metabolic regulation, sensory reception, excretion by means of secretion
Rickets
Softening and weakening of bones from lack of vitamin D
Layers of epidermis
Stratum Basale, stratum Spinosum, stratum Granulosum, stratum Lucidum, stratum Croneum
Types of cells in Stratum Basale:
Keratinocyte, Melanocyte, tactile (merkel)
Keratinocyte
Most abundant cell type in epidermis. Found throughout all the epidermal strata. Get their name from their ability to synthesize the protein keratin
Keratin
A family of fibrous structural proteins that are both tough and insoluble
Cytokeratin
Keratin found in epidermal cells
Melanocytes
Long branching processes and see scattered among the basal cells of the stratum Basale. Produce melanin
Melanin
Pigment in the skin
Tactile cells
Few in number and sedative to touch. Located in the stratum Basale.
Merkel cells
Few in number and sensitive to touch. Located in the stratum Basale. Also known as tactile cells
Epidermal dendritic cells
Small population of immune cells
Vitamin D is essential for the processing of what
Calcium and phosphorus
Excessive sunlight can lead to:
Suppressed immunity, skin damage, increased risk of cancer
The skin can detect
Heat, cold, touch, pressure, texture, and vibration
The skin eliminates waste products such as:
Water, salt, urea
Stratum germinativum
Stratum Basale and stratum Spinosum together
Stratum Spinosum contains what type of cells
Keratinocytes and phagoctic cells (epidermal dendritic cells
Stratum granulosum
Consists of 3 to 5 layers of Keratinocytes. The cells begin to die and fill up with keratin.
Keratinization
When Keratinocytes die and fill up with keratin
Stratum lucidum
Thin,clear region of two to three layers of flat dead cells. Only found on soles, palms, and lips
Stratum corneum
20 - 30 layers of flattened, dead, scale like cells which contain large amounts of Keratin. Most superficial layer
Cornification
After keratinization when cells become hard
How does a callus form?
Friction at the skin surface stimulates additional mitotic activity if the stratum Basale, resulting in thicker skin in that localized area
Where does tattooing occur?
Below stratum basale
What does thick skin not contain?
Hair follicles and sebaceous glands
What does thick skin contain?
Sweat glands
What does thin skin contain?
Sweat glands, hair follicles, and sebaceous glands
What contributes to skin color?
Melanin, hemoglobin, carotene
What does melanin protect?
DNA from UV light
Where is hemoglobin found?
In Erythrocytes
Erythrocytes
Red blood cells
What color is deoxygenated blood
Dark red or maroon
What does blood appear blue?
Subcutaneous fat absorbs low-frequency light; permitting only the highly energetic blue wavelengths to penetrate through to the dark vein
What is carotene?
The weakest of the skin pigments. It’s a yellow-orange pigment that is acquired by eating various yellow-orange vegetables.
Where does carotene normally accumulate?
Inside Keratinocytes of the stratum corneum and within the subcutaneous fat
What does carotene convert to?
Vitamin A
Albinism
A lack of melanin production caused by an inherited recessive condition which an enzyme needed to synthesize melanin is nonfunctional, so privileged Melanocytes cannot produce melanin
Vitiligo
Depigmentation of parts of the skin. It occurs when Melanocytes die or are unable to function. The cause of vitiligo is unknown, but research suggests that it may arise from autoimmune, genetic, oxidative stress, neural, or viral causes.
Cyanosis
Caused by reduced oxygenation of hemoglobin in blood vessels. Skin turns blue
Acrocyanosis
Cyanosis in the hands or extremities
Pallor
Caused by a deficiency of erythrocytes, a deficiency of hemoglobin, or both
Jaundice
Caused by the hemoglobin breakdown product bilirubin
Erythema
Caused by increased blood in the dermis because of dilated blood vessels. Can be causd by sunburn, excess heat, emotions, or infections
Postmortem lividity
When blood pools at the lowest point of the body 1 to 2 hours after death. Initially blanches when squeezed. After 8 hours will not blanch when squeezed.
Livor mortis
When blood pools at the lowest point of the body 1 to 2 hours after death. Initially blanches when squeezed. After 8 hours will not blanch when squeezed.
Dermis
Deeper and thicker layer than the epidermis
Dermis has how many layers?
- Papillary layer and reticulatr layer
What does the dermis do?
Nourish the living portion of the epidermis and the numerous supportive components of the skin
What is contained within the dermis?
Collagen, vascular tissue, many epithelial glands, it’s extensively innervated, and has elastic fibers
Papillary layer
Upper layer of the dermis
Stratum papillarosum
Upper layer of the dermis
Dermal papillae
Projections which extend from the upper layer of the dermis into the epidermis. They interlock with epidermal ridges
Epidermal ridges
Deep inward projections of the epidermis
What causes friction ridges?
The upward and downward waves of the papillary layer that contribute to friction ridges
Does the papillary layer contain nerve endings?
Yes
Reticular layer
The deeper major portion of the dermis and extends from the thin, overlying papillary layer to the underlying subcutaneous layer.
Stratum reticularosum
The deeper major portion of the dermis and extends from the thin, overlying papillary layer to the underlying subcutaneous layer.
Another word for Reticular layer is
Stratum reticularosum
Reticular means?
Network. Referring to the mesh work of collagen and elastic fibers that contribute you the skins strength and elasticity
Striae
Stretch marks
Linea albincantes
Stretch marks
Causes of striae
Rapid stretching of the Reticular layer. Pregnancy, teen growth spurts, excessive weight gain, and anabolic steroid use. It tears the collagen fibers
Lines of cleavage
Linear orientation of collagen and elastic fibers in different regions of the body.
Tension lines
Linear orientation of collagen and elastic fibers in different regions of the body.
Causes of Linea albicantes
Rapid stretching of the Reticular layer. Pregnancy, teen growth spurts, excessive weight gain, and anabolic steroids
Bed sores
Decubitus ulcers
Decubitus ulcers
Bed sores
What cause Decubitus ulcers?
Pressure cutting off blood circulation to boney parts of the body
Subcutaneous therapeutic injection
Injection in the subcutaneous blood supply
Liposuction
When a blunt hollow tube is roughly inserted into the subcutaneous layer so that fat can be auctioned out
What does the hypodermis do?
Cushions, insulates, and helps regulate temperature
What do nails do?
Serve to protect the digits and assist in grasping small objects.
What forms nails?
Hardened, transparent, stratum corneum
The cells that form the nails are?
Densely packed together and filled with parallel fibers of hard keratin
Why do toenails grow slower than finger nails?
The blood supply to the toes is less than to the fingers
Another word for hair?
Pili
What is pili?
Hair
Where is piling absent?
Sides and soles of the feet, the lips, the sides of the fingers and toes, and portions of the external genitalia
Pilus
Single hair
What is piling composed of?
Keratinized cells growing from a hair follicle that extends deep into the dermis, often projecting into the underlying subcutaneous layer.
Where is hair produced?
Epidermal layer
Hair bulb
Consists of epithelial cells and is a swelling at the base of the hair follicle where the hair originates
Root
The remainder of the hair within the follicle but outside the bulb
Shaft
The portion of the hair that extends beyond the skin surface
Hair follicle
An oblique tube the that surrounds the hair. The follicle always extends into the dermis and sometimes into the subcutaneous layer. it has an inner sheath of epithelial cells
Arrector pili muscles
Thin ribbons of smooth muscle extending from the connective tissue sheath around the hair follicle to the connective tissue of the dermal papillae.
What do Arrector pili muscles do?
Arrector pili muscles contract pulling on the follicles, which elevates the hairs and cause “goose bumps”
Functions of hair
Protection, heat retention, facial expression, sensory reception, visual identification, chemical signal dispersal
Hairs help disperse what?
Pheromones
What detects pheromones?
The vomeronasal organ in the human nose
What determines hair color?
Hair color is determined by the type and amount of pigment produced in the stratum Basale cells at the base of the hair follicle
What leads to darker hair?
More melanin
What causes red hair?
A special iron based pigment
What causes gray hair?
A gradual reduction of melanin
What causes white hair?
A lack of pigment entirely
What are the causes of hair loss?
Dietary deficiency, high fever, radiation, drugs, aging, genetics, or changes in hormone levels
Where do the glands off the skin originate and where are they located?
They originate from the epidermal layer and they are located in the dermis
Skin glands secrete substances through ducts, so they are called:
Exocrine glands
Sweat glands are also called what?
Sudoriferous glands
What are mammary glands?
Specialized Sudoriferous glands that secrete milk during lactation
What are ceruminous glands?
Modified Sudoriferous glands that secretes cerumen
What is cerumen
Earwax
Cerumen contains what?
Lysozyme
What does Lysozyme do!?
It’s an enzyme capable of destroying bacterial cells
Another name for oil glands is?
Sebaceous glands.
What is sebum?
An oily, waxy secretion on the surface of a hair follicle to keep the hair and skin supple
Dandruff is caused by the test that belongs to the genera of
Pityrosporum or malassezia
