Chapter 6 Integumentary System Flashcards
functions of skin
Protection (physical and Chemical
Regulation of body temperature
Contains sensory receptors
Excretion and absorption
Synthesis of Vitamin D
Stores Nutrients
How thichk is the integumentary system
what tissue types did the integumentary system contain
all 4
how large is the integumentary system
22 square feet
what are the two layers of the skin?
Epidermis and dermis
What tissue are the Epiderms made up of
Epithelial
What tissues are the dermis made up of
mostly connective, with some nerve, muscle, and epithelial
Subcutaneous tissue
a layer of adipose and areolar tissue (also known as hypodermis or subQ)
Characteristics of Epidermis
Mostly stratified squamous epithelium, it contains no blood vessels, 4 types of cells, 5 distinct strata (layer) of cells
What are the four types of cells in the epidermis
Keratinocytes, melanocytes, Langerhans cells, and Merkel cells
Keratinocytes
90% of the epidermis, made from stem cells of skin and produce keratin, which strengthens and waterproofs the skin.
Melanocytes
8% of the epidermis; produces the pigment melanin
Langerhan cell (dendritic)
Comes from bone marrow, and provides immunity
Merkel cells (tactile cells)
Found in the deepest layer (Basale layer) forms touch receptors with sensory neurons.
what are the 5 layers of the epidermis?
Corneum, Lucidum, Granulosum, Spinosum, Basale
Basale Layer
is the deepest layer of the epidermis, a single layer of cells, attached to the basement membrane, contains Merkel cells, melanocytes, and keratinocytes, it is the only are of cell division in the epidermis
Spinosum Layer
8 to ten layers of keratinocytes held together by desmosomes, these cells take in the pigment melanin by phagocytosis from nearby melanocytes, Langerhan cells found here help with immunity.
Granulosum layer
3-5 layers of flat dying keratinocytes, keritinization occurs as cells move upward
Keratinization
Nucleus and Organelles degenerate, cells fill with keratin and die
Lucidum Layer
Only found in thick skin (soles of feet and palms), 3-5 layers of clear, flat, dead cells
Corneum layer
25 to 30 layers of flat dead cells filled with keratin, acts as a barrier to light, heat, water, chemicals, and bacteria
what is produced when stem cells deivide
keratinocutes
keratinocytes are filled with what
keratin
how long does it take for cells to grow and be shed
4 weeks (2 to get to the corneum, 2 more before they shed)
Psoriasis
chronic skin disorder in which cells shed in 7-10 days as flakey silvery scales, abnormal keratin produced
Skin grafts
covering a wound with a piece of healthy skin
What would cause the need for skin grafts
damage of stem cells
Autograft
skin graft from self
isograft
skin graft from twin
Autologous skin
transplantation of skin from self, grown to size in a lab
How do melanocytes make melanin
By converting turosine to melanin
What increases melanin production
UV in sunlight
What causes freckles
a patch of melanocytes
Albanism
Lack of tyrosinase; no pigment
vitilligo
auto immune loss of melanocutes in areas of the skin, produces white patches.
where is Carotene found
in the stratum corneum and the dermis
What is Carotine
Yellow-Orange pigment (precursor of vitamin A)
If other pigments are not present epidermis is translucent so pinkness will be evident
Hemoglobin
Red, Oxygen carrying pigment in blood
Jaundice
Yellowing of the skin and whites of eyes, caused by buidup of yellow bilirubin in blood from liver disease
Cyanotic
Bluish color to nail beds and skin, hemoglobin depleted of oxygen looks purple-blue
Erythema
Redness of skin due to enlargment of capilaries in the dermis
Papillary Region Function
anchors epidermis to dermis, contains cappilaries theat feed epidermis, and contains messner’s corpuscels (touch) and free nerve endings (pain and temperature)
Papillary region location and makeup
top 20% of the dermis, comosed of lood connective tissue and elastic fibers
Reticular Region
contains interlacing collagen and elatic fibers, contains, filled with oil glands, sweat gland ducts, a little bit of fat and hair folicalles
What is in the Reticular Region
contains interlacing collagen and elatic fibers, contains, filled with oil glands, sweat gland ducts, a little bit of fat and hair folicalles
Reticular Region Function
Provides strength, extensability and elasticity to the skis
What causes differences in skin color
different type of melanin produced
Freckles
Melanocytes in a patch
albinism
No tyrosinase (pigment)
Vitiligo
autoimmune loss of melanocytes in areas of skin, produces white patches
Carotene
Yello-orange pigment found in stratum corneum and dermis
hemoglobin
red, oxygen carrying pigment in blood cells
Jaundice
Yellowish color to skin and whites of eyes; caused by buildup of yellw bilirubin in blood from liver disease
Cyatonic
Bluish color to nails and skin; caused by depletiokn of oxygen which makes hemoglobin look purple-blue
Erythema
redness of skin due to enlargement of cappillaries in dermis; shows during inflammation, infection, allergy, or burns
Shaft (hair)
visible segment of hair
Follicle
Surrond root of hair; bulb shaped
Arrector Pili
Smooth muscle in dermis that contracts with cold or fear and makes goosebumps
2 stages of Hair growth cycle
Growth stage and resting stage
how long does the growth stage last
2-6 years
how long does the resting stage last
3 months
What is the cause of hair color
melanin produced by melanocytes in hair bulb
Functions of hair
- Prevents heat loss
- decreases sunburn
- eylashes protect eyes
- touch receptors sense touch
4 exocrine glands found in the dermis
- Sebaceous (oil)
- Sudoriferous (sweat)
- Ceruminous (wax)
- Mammary (milk)
Secretory portion of the sebum
Sebaceous Glands
Where are sebaceous glands
open onto hair shafts
what is sebum made out of
Cholesterol, proteins, fats and salts
What is the function of sebum
keeps hair soft and pliable; inhibits growth of bacteria and fungi
Acne
- bacterial inflammation of glands
- secretions stimulated by horomones at puberty
Where are Eccrine glands found
most areas of the skin
Purpose of eccrine glands
regulate body temperature
where are Apocrine glands
armpit and pubic regions
Sweat gland associated with Body Odor
Apocrine glands
What causes body oder
bacteria metabolizing the sweat
Ceruminous gland
modified sweat glands that produce waxy secretion in the ear
mammary gland
secretes milk
what are nails made of
tightly packed keratinized cells
how fast do nails grow
1mm per week
where is thick skin
palms of hands and soles of feet
what does thick skin have that thin doesn’t
stratum lucidum
general functions of skin
Regulation of body temperature
Contain Sensory receptors
Excretion and absorption
Synthesis of vitamin D
Stores nutrients
how large of the skin
22 square feet
how heavy is the skin
15% of body weight
thermoregulation
- Releasing of sweat onto the skin
- Adjusting flow of blood to the body surface
- Shivering and constriction of surface vessels
how is vitamin D created
absorbed by skin, than transformed by liver and kidnies into calcitrol
how is vitamin D created
absorbed by skin, than transformed by liver and kidnies into calcitrol
4 phases of deep wound healing
Hemeostasis, Inflamation, Proligerative, Maturation
4 phases of deep wound healing
Hemeostasis, Inflamation, Proligerative, Maturation
Hemeostasis
Blood vessels tighten (vasoconstriction), Fibrin (protein) forms a blood clot on the skin
Inflimation
Blood vessels dilate (vasodilation), white blood cells (macrophages) arrive to phagocytize bacteria and release growth factors.
Proliferative
Fibroblasts arrive and synthesize collagen fibers to regenerate the dermis.
Maturation
Adult stem cells divide to regenerate tissue.
Maturation
Adult stem cells divide to regenerate tissue.
Hypertrophic scars
remain within origional wound
Keloid scar
extends beyon original wound
3 forms of skin cancer
basal cell carcinoma
squamous cell carcinoma
malignant melanomas
basal cell carcinoma
rarely metastasize
squamous cell carcinoma
May metastasize
malignant melanomas
metastasize rapidly
what causes Pressure Sores
constant deficiency of blood flow to tissue
