A&P Chapter 5: Integumentary System Review
First-degree: Epidermis only damaged Swelling, redness, pain
1
Free nerve endings (pain, temperature...)
1
Hyponychium
1
Melanocyte
1
Functions of Integumentary System
1. Protection 2. Body Temperature Regulation 3. Cutaneous Sensation 4. Metabolic Functions 5. Blood Reservoir 6. Excretion
Cutaneous vascular plexus
2
Stratum spinosum Several layers of keratinocytes unified by desmosomes. Cells contain thick bundles of intermediate filaments made of pre-keratin.
3
corneum, granulosum, spinosum, basale
A needle would pierce the epidermal layers of the forearm in which order? A) basale, spinosum, granulosum, corneum B) basale, spinosum, granulosum, lucidum, corneum C) granulosum, basale, spinosum, corneum D) corneum, granulosum, spinosum, basale
The stratum basale is composed of what?
A single layer of cells in contact with the dermis
What is true of the subcutaneous layer?
A. Contains many blood vessels B. Permits independent movement of deeper structures C. Contains large amounts of adipose tissue D. Is well supplied with nerves that pass into the skin
sebaceous glands
Acne is a disorder associated with ________.
Which are larger, eccrine or apocrine sweat glands?
Apocrine
Stratum Lucidum (Clear Layer)
Appears as a clear translucent band just above the stratum granuosum. 2 to 3 rows of flat, dead keratinocytes.
It appears to be genetically determined and sex-linked, and is possibly caused by a delayed-action gene that responds to DHT and alters normal metabolism.
Balding men have tried all kinds of remedies, including hair transplants, to restore their lost locks. Explain the cause of male pattern baldness.
Stratum basale
Basal layer of epidermis. Responsible for cell division and replacement
Blood vessels of the dermis play an important role in regulating what?
Body temperature and blood pressure
Vitamin ad is essential for the maintenance and growth of what?
Bones and the skeletal system
Vitamin D helps with the absorption of what?
Calcium and phosphate
Medulla
Central core of hair, consists of large cells and spaces. Soft keratin absent in fine hairs.
Stratum Basale (Basale Layer)
Deepest epidermal layer firmly attached to the dermis, Single row of stem cells, Also called stratum germinativum: cells undergo rapid division, Journey from basal layer to surface Takes 25-45 days, 10 - 25% made of melanocytes
Rickets
Disease caused by vitamin D deficiency
Second Degree Burns
Epidermal and upper dermal damage. Blisters appear.
_ produces the pinkish color in skin.
Hemoglobin
lucidum
If a splinter penetrated the skin into the second epidermal layer of the sole of the foot, which cells would be damaged?
It converts modified epidermal cholesterol to a vitamin D precursor important to calcium metabolism
In addition to protection (physical and chemical barrier), the skin serves other functions. Which of the following is another vital function of the skin?
Excretion
Limited amounts of nitrogenous wastes and salt are eliminated in sweat.
Hair Follicles
Longitudinal view of the hair bulb in the follicle from the epidermal surface into dermis. Two-layered wall: outer connective tissue root sheath, inner epithelial root sheath, Hair bulb: expanded deep end
What is the hypodermis composed of?
Loose irregular connective tissue, adipose cells interlaced with blood vessels
An albino individual lacks the ability to produce __.
Melanin
Melanocytes produce what?
Melanin
What protects skin from excessive sunlight?
Melanin
Skin coloration is due to which 2 pigments in normal circumstances?
Melanin and hemoglobin
The stratum basale (basal layer) is the _ layer.
Mitotic
Melanoma
Most dangerous. Involves melanocytes. Highly metastatic and resistant to chemotherapy. Treated by wide surgical excision accompanied by immunotherapy. Characteristics (ABCD rule) A: Asymmetry; the two sides of the pigmented area do not match B: Border exhibits indentations C: Color is black, brown, tan, and sometimes red or blue D: Diameter is larger than 6 mm (size of a pencil eraser)
Efferent nerves
Motor nerves. Go to muscles or glands
Sebum
Oily holocrine secretion. Bactericidal. Softens hair and skin.
What are the functions of skin?
Physics protection, hydroregulation, thermoregulation, cutaneous absorption, synthesis, sensory reception, communication
Hair or Pili
Produced by hair follicles, consists of dead keratinized cells. 3 Layers of keratinized cells (medulla, cortex, cuticle) Functions: Alerting the body to presence of insects on the skin, guards scalp against physical trauma, heat loss, and sunlight Distribution: Entire surface except palms, soles, lips, nipples, and portions of external genitalia. Contains hard keratin; more durable than soft keratin of skin Hair pigments: melanins (yellow, rust brown, black) Gray/white hair: decreased melanin production, increased air bubbles in shaft
The layer of the skin that contains bundles of collagen fibers and the protein elastin and is responsible for the strength of the skin
Reticular layer
Stratum Reticularosum
Reticular layer. Most of the dermis. Fairly distensible, but if stretched too far, it tears causing stretch marks
Body is divided into 11 areas Each area accounts for 9% of total body area 12th area (surrounding genitals) accounts for 1% Rule of Nines provides a way to estimate fluid loss that accompanies burns Is also used to designate which burns are "critical"
Rule of Nines
Nail
Scalelike modification of the epidermis on the distal, dorsal surface of fingers and toes.
Mammary Glands
Secrete milk
Afferent nerves
Sensory nerves. Aid in proprioception (where you are in space). All info goes to central nervous system ( temp, pain, pressure)
Temp Up: dermal capillaries dilate, sweat glands increase excretion Temp down: Dermal capillaries constrict, subcutaneous fat insulates
Skin Function: Regulates body temp
Hydroregulation
Skin is virtually waterproof, protecting from dehydration on dry land, and even from water absorption when immersed in water
hypodermis
Subcutaneous layer, attaches dermis to underlying tissue, adipose, areolar connective tissues (energy reserve and padding), vascular
Mammary glands are specialized __ glands that secrete milk during lactation under the influence of pituitary and ovarian hormones
Sudoriferous
False; mostly adipose
T or F: The hypodermis is composed of adipose and dense connective tissue.
False; eponychium
T or F: The hyponychium is commonly called the cuticle.
True
T or F: The most dangerous skin cancer is cancer of the melanocytes.
True
T or F: The outermost sheath of a hair follicle is the connective tissue root sheath.
True
T or F: The pinkish hue of individuals with fair skin is the result of the crimson color of oxygenated hemoglobin (contained in red blood cells) circulating in the dermal capillaries and reflecting through the epidermis.
False; keratin
T or F: The protein found in large amounts in the outermost layer of epidermal cells is collagen.
False; capillaries underneath
T or F: The reason that the nail bed appears pink is the presence of a large number of melanocytes in the underlying dermis.
Cutaneous Sensations
Temperature, touch, and pain
What are racial variations in skin color are due to?
The amount of melanin produce and the distribution of melanin in the skin
papillary
The dermis is composed of the reticular and ________ layers.
Stratum corneum
The layer of the epidermis where the cells are considered protective but nonviable.
external root sheath
The major regions of a hair shaft include all of the following except ________.
dermal papillae
The papillary layer of the dermis is connective tissue heavily invested with blood vessels. The superficial surface has structures called:
Hemoglobin
The pinkish hue of fair skin, refects oxygenated hemoglobin in the blood cells circulating through dermal capillaries.
Dermis (b)
The second major skin region, is strong flexible connective tissue. Its cells are fibroblast, macrophages and occasional mast cells. Richly supplied with nerve fibers, blood vessels, and lymphatic vessels. Has two layers, papillary and reticular layers
Thermoregulation
The skin plays a crucial role in the regulation of body temperature
Protection
Three types of barriers: 1. Chemical (Low pH secretions (acid mantle) and defensins retard bacterial activity) 2. Physical/Mechanical (Keratin and glycolipids block most water and water- soluble substances limite penetration of skin by lipid-soluble substances, plant oleoresins (e.g., poison ivy), organic solvents, salts of heavy metals, some drugs) 3. Biological (Dendritic cells, macrophages, and DNA)
burns
Tissue damage due to denaturing of proteins & cell death. heat, electricity, radiation, chemical
Blood vessels in dermis supply nutrients where?
To the mitotically active stratum basale of epidermis
__ is essential for muscle contractions of the muscular system
Vitamin D
Synthesis of vitamin D
Vitamin D is synthesized from dehydrocholesterol in the presence of UV light
Perspiration produced by merocrine sweat glands contains what?
Water, electrolytes, and waste products
Do all individuals of similar size have the same number of melanocytes?
Yes
Where is apocrine found?
axillery and pubic regions
What structure anchors the epidermis to the dermis?
basement membrane
myoepithelial
cells contract when stimulated to force sweat out Merocrine secretion (by exocytosis!)
When the sebaceous gland is under active what kind of skin do you have?
dry skin
Where is the cebaceous gland located?
ear canal
What determines the thickness and pattern of distribution of hair?
genetics and hormonal influences
What are the accessory organs of the integumentary system?
hair, nails, nerve receptors
Which hair guards your scalp from injury and the sun?
head hair
What type of cells adsorb damaging UV rays?
melanocytes
What are the steps in healing an epidermal wound?
migration of epidermal cells across wound cap, cells from stratum basale migrate up edges of wound, cells from stratum basale divide until they meet in the middle (realize contact inhibition)
Does the epidermis contain blood vessels?
no, it is avascular
Which hair protects against inhaling insects and foreign particles?
nostril hair
structure composed of 2 or more tissues with a specific function. Most have recognizable shapes
organ
What is the integumentary system composed of?
organs; skin, hair, nails
What substance waterproofs, keeps the hair and skin moist, and kills bacteria?
sebum
What is the largest organ of the body in area and weight?
skin
Which layer is superficial to the stratum basale and contains 8-10 layers of keratinocytes closely packed?
stratum spinosum
What are striae?
stretch marks
Describe the function of excretion of wastes
sweat glands release waste
What occurs in the stratum lucidum?
thickened skin on the palms and soles due to additional wear and tear, most cells are dead and keratin precursors develop
What is the structure of the epidermal layer?
thin, superficial layer of mainly stratified squamous
Epidermis (Epithelium)
1
Papillary Layer (Areolar CT)
1
Stratum corneum Most superficial layer; 20-30 layers of dead cells represented only by flat membranous sacs filled with keratin. Glycolipids in extracellular space.
1
Subpapillary vascular plexus
1
follicle wall
1
hair
1
hair matrix Mitotic (dividing) region of hair
1
3 ways excessive heat is lost from body
1. Through radiation from dilated blood vessels 2. Secretion and evaporation of perspiration 3. Convection and conduction of heat directly through the skin
The Skin
1.5-4.0 millimeters (mm), composed of two distinct regions, the epidermis and dermis
whitish material produced by fetal sebaceous glands
15) Vernix caseosa is a ________. A) substance contributing to acne during adolescence B) whitish material produced by fetal sebaceous glands C) coat of fine, downy hair on the heads of balding men D) cheesy-looking sudoriferous secretion on the skin of newborns
Dermis
2
Dermis (Connective Tissue)
2
Keratinocytes
2
Nail matrix
2
Pacinian Corpuscle (deep pressure)
2
Sebaceous (oil) gland
2
Second-degree: Epidermis and upper dermis damaged Red, painful, blisters
2
Stratum granulosum Three to five layers of flattened cells, organelles deteriorating; cytoplasm full of lamellated gran- ules (release lipids) and keratohyaline granules.
2
hair
2
hair papilla Extension of connective tissue Contains capillaries
2
How many types of suderiforous glands are there and what are they?
2 eccrine and apocrine
How many main parts does the skin consist of and what are they?
2 epidermis and dermis
Stratum Corneum (Horny Layer)
20 to 40 cell layers of dead, flat keratinized, membranous sacs, accounts for up to 3/4s of epidermal thickness. Functions: Protects from abrasion and penetration, Waterproofs, Barrier against biological, chemical, and physical assaults
What is stratum corneum?
20 to 50 rows, flattened, dead cells, cells are filled with keratin and the ones that are lost by wear and tear are replaced by deeper cells
Stratum corneum is composed of what?
25-30 layers of flattened, scalelike cells
Stratum spinosum
2nd layer of epidermis
Epidermal dendritic cell (Langerhans cell)
3
Eponychium (cuticle)
3
Hair follicle receptor (hair movement)
3
Hypodermis (mostly Adipose Tissue)
3
Reticular Layer (Dense Irregular CT)
3
Sweat Gland
3
Third-degree: Involve full thickness of skin Nerve endings destroyed
3
melanocyte
3
How many types of glands are there and what are they?
3 sebaceous (oil), ceruminous, and suderiforous (sweat)
What is stratum granulosum
3 to 5 rows, partially flattened cells that contain proteins or granules that are precursors to keratin
How often do we get a new epidermis?
35-45 days
Stratum granulosum (granular layer)
3rd layer of epidermis, made of 3-5 flattened rows of cells
Lunule
4
Meissner's Corpuscle (light touch) Hairless skin only
4
Nail
4
Stratum basale Deepest epidermal layer; one row of actively mitotic stem cells (basal cells); some newly formed cells become part of the more superficial layers. See occasional melanocytes and epidermal dendritic cells.
4
Tactile (Merkel) cell
4
How many layers does the epidermis have in most places and what are they?
4 stratum corneum, stratum granulosum, stratum spinosum, stratum germanium (basale)
How long does the process of keratinization take?
4 weeks
The epidermis is composed of how many layers?
5 layers in thick skin, 4 layers in all other areas of body
Sweat
99% water + salt, antibacterial proteins (dermcidin), trace metabolic wastes. Secretion stimulated by heat or fear
specialized phagocytic cell
A Langerhans' cell is a ________.
Cortex
A bulky layer surrounding the medulla, consists of several layers of flattened cells
The effects of aging on the skin include what effect on the sebaceous glands?
A decline of activity
Addison's
A summertime golden bronze tan may not be a tan at all; especially if the skin appears almost metallic bronze, it may be the result of ________ disease.
Reticular Layer
Accounts for 80% of the thickness of the dermis, it is coarse, irregularly arranged, and dense fibrous connective tissue. Collagen fibers provide strength and resiliency, Elastic fibers provide stretch-recoil properties.
resident macrophage-like cells whose function is to ingest antigenic invaders and present them to the immune system
Although the integument is a covering, it is by no means simple, and some of its functions include ________.
in the axillary and anogenital area
Apocrine glands, which begin to function at puberty under hormonal influence, seem to play little role in thermoregulation. Where would we find these glands in the human body?
Mammary glands are a type of __ gland
Apocrine sweat glands
Most body odor is the result of bacterial metabolism of the secretions produced by __ glands
Apocrine sweat glands
Merkel or Tactile Cells
Are present at the epidermal-dermal junction. Shaped like a spiky hemisphere. Each cell is associated with a disclike sensory nerve ending. (touch receptors)
Epidermal Dendritic Cells
Arise from bone marrow and migrate to the epidermis. Also called Langerhans cells. Functions: they ingest foreign substances and are key activators of the immune system.
How is hair formed?
As epidermal cells divide and grow, older cells are pushed towards the surface. As they move upward they move further from the dermal's nutrients so they begin to keratinize and die. The remains extend away from the skin surface creating the hair shaft
What controls the eccrine sweat glands?
Autonomic nervous system
Where are apocrine sweat glands found?
Axillary and pubic regions where they secrete into hair follicles
Squamous cell carcinoma: Second most common Arises from stratum spinosum cells Scaly, red, raised patch Grows rapidly, likely to metastasize
B
Sweat is mostly an odorless watery secretion produced by eccrine and apocrine glands. The odor usually arises due to the metabolic activities of bacteria on the surface of the skin.
Billions of consumer dollars are spent for deodorants and antiperspirants each year. Explain the production of body odors frequently associated with axillary skin.
First step of integumentary repair following an injury
Bleeding and inflammation
5 things contained in dermis
Blood vessels, sweat glands, oil secreting glands, nerve endings, hair follicles
Melanin
Brown-black pigment produced in the melanocytes of the stratum basale
eschar
Burned, dead skin
How is the skin innervated?
By both motor (efferent) nerves and sensory (afferent) nerves
Melanoma: Highly metastatic, resists chemotherapy Increasing in incidence! Arises from melanocytes Identified by the ABCD rule
C
Melanocytes Synthesize melanin, the protein that gives skin tan/brown/black pigment
Cells of the skin: 1
Melanosomes: Melanin accumulates in granules called melanosomes, that are passed onto keratinocytes Found in stratum basale, but long extensions reach more superficial strata
Cells of the skin: 2
The skin takes on a bronze or metallic appearance.
Changes in the color of skin are often an indication of a homeostatic imbalance. Which of the following changes would suggest that a patient is suffering from Addison's disease?
Keratohyalin
Chemical precursor to keratin
Terminal (Hair Type)
Coarse, long hair of eyebrows, scalp, axillary, and pubic regions (and face and neck of males).
The repair of the dermis begins as fibroblasts produce ___
Collagen fibers
What reinforces the hypodermis?
Collagenous and elastic fibers
How can you detect fever or shock?
Color and temperature of skin
Dermal Papillae
Contain Capillary loops, Meissner's corpuscles (touch receptors), Free nerve endings (pain receptors). Indent overlying epidermis.
seborrhea
Cradle cap in infants is called ________.
Hair (image)
Cross section of a hair and hair follicle.
Sensory reception
Cutaneous receptors are abundant in dermis and hypodermis of the face, palms and fingers of hands, soles of feet, and genitalia. They are less abundant song back and back of neck
Where is the vascular supply found?
Dermis
The appearance of visible, silvery-white scars is an indication of stretching of the dermis.
Despite its apparent durability, the dermis is subject to tearing. How might a person know that the dermis has been stretched and/or torn? A) Because the pain is acute due to the large number of Meissner's corpuscles. B) The appearance of visible, silvery-white scars is an indication of stretching of the dermis. C) The blood vessels in the dermis rupture and the blood passes through the tissue, causing "black and blue marks." D) The stretching causes the tension lines to disappear.
Differences in skin color among individuals are the result of _.
Differences in the number of melanocytes
Cerumen
Ear wax- water and insect repellant
What are the 2 types of sudoriferous glands?
Eccrine glands and Apocrine glands
Developmental Aspects: Fetal
Ectoderm - epidermis , Mesoderm - dermis and hypodermis , Lanugo coat: covering of delicate hairs in 5th and 6th month, Vernix caseosa: sebaceous gland secretion; protects skin of fetus.
What is the dermis composed of?
Elastic and collagenous fibers arranged in a dense irregular fashion
The protein that permits stretching and recoiling of the skin
Elastin
Third Degree Burns
Entire thickness of skin damaged. Gray-white, cherry red, or black. No initial edema or pain (nerve endings destroyed). Skin grafting usually necessary.
First Degree Burns
Epidermal damage only, Localized redness, edema (swelling), and pain.
Developmental Aspects: Old Age
Epidermal replacement slows, skin becomes thin, dry, and itchy. Subcutaneous fat and elasticity decrease, leading to cold intolerance and wrinkles, Increased risk of cancer due to decreased numbers of melanocytes and dendritic cells.
Layer of skin that provides protection against bacteria as well as mechanical injuries
Epidermis
What are the three layers of the skin?
Epidermis, Dermis, and Hypodermis/Subcutaneous
Function of Eccrine sweat glands
Evaporative cooling for body temperature regulation
What causes hair to get greasy?
Every hair follicle has a sebaceous gland
eyebrow follicles are only active for a few months
Eyebrow hairs are always shorter than hairs on your head because ________. A) they grow much slower B) eyebrow follicles are only active for a few months C) the vascular supply of the eyebrow follicle is one-tenth that of the head hair follicle D) hormones in the eyebrow follicle switch the growth off after it has reached a predetermined length
Outermost Cuticle
Formed from a single layer of cells that overlap one another from below the shingles on a roof. Provides strength and helps keep inner layers tightly compacted.
pigmented nevi
Freckles and moles are small accumulations of melanin
Where do the cells of stratum granulosum get their granular appearance?
From granules filled with keratohyalin
UV exposure stimulates production of a precursor to Vit. D, essential for bone health, inhibit non-skin cancers, autoimmune diseases, heart disease
Function: Vitamin D metabolism
Chemical Barrier: Acid mantle (low pH of skin secretions) Cellular Barrier: Epidermal dendritic cells, dermal macrophages Infectious Barrier: normal colonizing bacteria crowd out 'bad' UV: melanin prevents DNA damage
Function: protection
protection vitamin D metabolism thermoregulation others
Functions of the skin
Hair Growth
Growth phase (weeks to years) followed by regressive stage and resting phase (1-3 months), Growth phase varies (6-10 years in scalp, 3-4 months in eyebrows)
Vellus
Hair that lacks pigment and is often called "immature hair."
Accessory structures of the skin
Hair, nails, glands
Functions of Perspiration produced by merocrine glands
Helps cool body when it evaporates and helps to prevent bacteria from colonizing the skin
Burns are classified according to their severity or depth. For example, in first-degree burns, only the epidermis is damaged; in second degree burns, the epidermis and upper dermis are damaged; in third degree burns, there is widespread damage of epidermis and dermis.
How are burns classified? Give an example.
Dermicidin has an effect on many bacteria but not all. A low pH slows the bacteria's ability to reproduce and grow. The slowing allows the dermicidin more time to work and allows macrophages to work as well.
If eccrine sweat glands produce dermicidin, why produce a fluid with a pH of 4-6?
Keratinocyte enzymes can neutralize carcinogens that penetrate the epidermis. Keratinocytes are also able to convert topical steroid hormones to a powerful anti-inflammatory drug.
In addition to the synthesis of vitamin D, keratinocytes are able to carry out some other biologically important functions. Name at least two of these other functions.
Effects of ultraviolet radiation
Increased activity by melanocytes, production of cholecalciferol by epidermal cells, sunburn, chromosomal damage in Germinative cells or melanocytes
What causes blushing in fair skinned people?
Involuntary vasodilation of dermal blood vessels
Cutaneous absorption
Is fairly limited through skin.
Keratinocytes produce what?
Keratin
Stratum lucidum is completely filled with _.
Keratin
What does the integumentary system synthesize?
Keratin, melanin, vitamin D
The epidermis is composed of what kind of epithelium?
Keratinized stratified squamous
The most abundant cells in the epidermis
Keratinocytes
What type of cells help protect the skin and underlying tissue from heat, microbes, and chemicals?
Keratinocytes
What type of cells waterproof the body?
Keratinocytes
What 4 cell types compose the stratum basale?
Keratinocytes Melanocytes Tactile cells Nonpigmented granular dendrocytes
stratum germinativum
Keratinocytes - Cells of the Skin Arise from mitotic division in stratum basale As basal cells divide, keratinocytes pushed up through strata, becoming more fully keratinized
lamellated granules
Keratinocytes - Cells of the Skin Produce keratin and waterproof glycolipids
they produce a fibrous protein that gives the skin much of its protective properties
Keratinocytes are an important epidermal cell because ________.
Name the cells of the Epidermis
Keratinocytes, Melanocytes, Epidermal Dendritic cells (Langerhans' cells), and Merkel or tactile cells. MNEMONIC: Keran Massaged ED Langerhan's Muscles Tactfully
Basal Cell Carcinoma
Least malignant, most common, Stratum basale cells proliferate and slowly invade dermis and hypodermis, Cured by surgical excision in 99% of cases.
Apocrine sweat glands
Limited to axillary (armpit) and anogenital regions Larger, deeper, secrete into hair follicles Apocrine sweat also contains fatty substances and proteins Primary function may be sexual, little effect on thermoregulation
Dermis
Makes up the bulk of the skin, is a tough leathery layer composed mostly of fibrous connective tissue. Only the dermis is vascularized.
male hormones
Male pattern baldness has a genetic switch that turns on in response to ________.
are spidery-shaped cells in contact with cells in the stratum basale
Melanocytes ________.
accumulate the melanin granules on their superficial portion, forming a UV-blocking pigment layer
Melanocytes and keratinocytes work together in protecting the skin from UV damage when keratinocytes ________. A) provide the melanocyte with a protective shield against abrasion B) accumulate the melanin granules on their superficial portion, forming a UV-blocking pigment layer C) maintain the appropriate pH in order for the melanocyte to synthesize melanin granules D) maintain the appropriate temperature so the product of the melanocyte will not denature
Ceruminous Glands
Modified specialized apocrine glands found in the lining of the external ear canal. Secretion mixes with sebum and produces cerumen or earwax.
Merocrine (eccrine) sweat glands
Most numerous type of sweat gland Secretory part coiled in dermis, duct to opening (pore) at skin surface
Skin Cancer
Most skin tumors are benign (do not metastasize). Risk factors: overexposure to UV radiation, frequent irritation of the skin. Some skin lotions contain enzymes in liposomes that can fix damaged DNA. 3 types: Basal Cell Carcinoma, Squamous Cell Carcinoma, Melanoma
Vitamin D
Must be activated in the skin in order to enhance calcium metabolism.
1. eccrine 2. apocrine 3. ceruminous 4. mammary
Name the four kinds of sudoriferous glands.
Stratum corneum, lucidum, granulosum, spinosum, and basale.
Name the layers of the epidermis in order from the surface down.
diffusing through the tissue fluid from blood vessels in the dermis
Nutrients reach the surface of the skin (epidermis) through the process of ________.
The highest concentration of merocrine sweat glands would be found where?
On the palms of the hands
How do the structures of the integumentary system relate to its functions?
Outer layer - epidermis has keratinized protective layer; second layer- dermis has secretion glands, blood vessels, hair follicles and receptors; third layer - subcutaneous has fatty cushion.
Where are cutaneous receptors sparse?
Over the joints
What can be cutaneous lay absorbed through skin?
Oxygen, carbon dioxide, uv light, Nonpolar molecules
Hemoglobin
Oxygen-binding pigment found in red blood cells; in dermal capillaries gives skin pinkish hue
Vellus (Hair Type)
Pale, fine body hair of children and adult females.
In what areas of the body are there greater concentrations of nerve endings?
Palms of hands, lips, external genitalia
Which layer of dermis is closest to the basement membrane?
Papillary layer
Stratum Papillarosum
Papillary layer of dermis. Contains the blood vessels and nerves closest to the surface of the skin
Tactile cells
Pressure cells. Nervous system receptors that aid in touch reception
What is the primary function of skin?
Protection
Nonpigmented granular dendrocytes
Protective, macrophagic cells that ingest bacteria and other foreign debris and present foreign molecules (immunogens) to the immune system
How do the structures of the integumentary system work together to maintain homeostasis in the body?
Provides protection, regulation of body temperature (sweat or shiver), sensory reception, water balance, synthesis of vitamins and hormones and absorption of materials.
Apocrine sweat glands are not functional until when?
Puberty
Developmental Aspects: Adolescent to Adult
Sebaceous gland activity increases. Effects of cumulative environmental assaults show after age 30, Scaling and dermatitis become more common.
What regulates the production and secretion of sebum?
Sec hormones
Squamous Cell Carcinoma
Second most common, Involves keratinocytes of stratum spinosum. Most common on scalp, ears, lower lip, and hands. Good prognosis if treated by radiation therapy or removed surgically.
Melanomas are rare but must be removed quickly to prevent them from metastasizing.
Select the most correct statement concerning skin cancer. A) Most tumors that arise on the skin are malignant. B) Squamous cell carcinomas arise from the stratum corneum. C) Basal cell carcinomas are the least common but most malignant. D) Melanomas are rare but must be removed quickly to prevent them from metastasizing.
Stratum Spinosum (Prickly Layer)
Several cell layers thick, cells contain a weblike system of intermediate prekeratin filaments attached to desmosomes. Keratinocytes appear to have spines and are scattered among abundant melanin granules and Langerhans' cells.
What does excessive heat loss trigger and why?
Shivering response in muscles to increase body heat
1) touch, temp, pain 2) nitrogenous wastes and salt in sweat 3) blood resevoir
Skin Functions: others
Dark-skinned individuals: 1) produce more melanin 2) produce darker melanin 3) keratinocytes retain melanin longer
Skin pigmentations
Name the organs that are involved in the integumentary system.
Skin, hair, nails, and sebaceous (sweat and oil) glands
Age-related changes in skin
Slower keratinocyte replacement --> Thinner skin Skin produces less lubrication --> Dryer skin Elastic fibers clump --> Skin loses elasticity (ability to spring back to shape) Reduction in subcutaneous fat --> Cold sensitive, skin sags Decreased number of melanocytes --> Increased skin cancer Hair follicle cells stop dividing --> Thinning hair
Arrector pili
Smooth muscle attached to follicle, Responsible for "goose bumps"
Examples of nonpolar molecules that are readily absorbed into skin
Steroid hormones and fat soluble vitamins (A, D, E, K) and clinically (lipid soluble toxins, pesticides, hexane, benzene, medicinal patches)
2 layers of dermis
Stratum Papillarosum, Stratum Reticularosum
The layer of the epidermis that contains the melanocytes
Stratum germinativum
In which layers of the epidermis do mitotic divisions occur?
Stratum germinativum and stratum spinosum
Large quantities of keratohyalin would be found in the epidermal layer called the _.
Stratum granulosum
Linea albicans
Stretch marks
eccrine and apocrine
Sudoriferous (sweat) glands are categorized as two distinct types. Which of the following are the two types of sweat glands?
_ secrete perspiration onto the surface of the skin.
Sudoriferous glands
Ceruminous glands secrete cerumen, which is thought to deter insects.
Sudoriferous glands vary in distribution over the surface of the body. Which of the following is correct? A) Eccrine are the most numerous, being found primarily in the axillary regions. B) Apocrine glands are larger than eccrine, and empty secretions directly to the surface of the skin. C) Ceruminous glands secrete cerumen, which is thought to deter insects. D) Mammary glands are not considered a modified sweat gland.
Layers of the Epidermis (b)
Superficial to deep: Stratum Corneum, Stratum Lucidum, Stratum Granulosum, Stratum Spinosum and Stratum Basale. MNEUMONIC: Cora, Luci's Grandma, Spins Baseballs.
Epidermis
Superficial, protective layer of skin. Composed of epithelial cells, is the outermost protective shield of the body. A keratinized stratified squamous epithelium consisting of 4 distinct cell types and 4 or 5 distinct layers.
Sudoriferous glands
Sweat Glands - serve an important function in thermoregulation. up to 3 million per person. Two types of glands, eccrine and apocrine.
Metabolic Functions
Synthesis of vitamin D precursor and collagenase Chemical conversion of carcinogens and some hormones.
True
T or F: A physician is often able to detect homeostatic imbalances in the body by observing changes in the skin color.
False; apocrine
T or F: Ceruminous glands are modified merocrine glands.
False; sebaceous (oil) gland
T or F: Destruction of the matrix of the hair bulb would result in its inability to produce oil.
True
T or F: During the resting phase of hair growth, the matrix is inactive and the follicle atrophies.
True
T or F: Hair growth and density are influenced by hormones, nutrition, and, in some cases, lifestyle.
False; parallel
T or F: Incisions should be made across rather than parallel to cleavage lines produced by collagen fiber bundles.
False; second degree
T or F: Joe just burned himself on a hot pot. A blister forms and the burn is painful. Joe's burn would best be described as a third-degree burn.
True
T or F: Regardless of race, all human beings have about the same number of melanocytes.
False; papillary
T or F: Skin surface markings that reflect points of tight dermal attachment to underlying tissues are called epidermal ridges.
True
T or F: Sweat glands continuously produce small amounts of sweat, even in cooler temperatures.
True
T or F: The apocrine sweat glands are fairly unimportant in thermoregulation.
True
T or F: The dense fibrous connective tissue portion of the skin is located in the reticular region of the dermis.
False; dense irregular and areolar connective tissue
T or F: The dermis has a connective tissue and adipose layer that loosely binds the body together.
True
T or F: The dermis is rich in blood vessels and nerve fibers.
False
T or F: The skin is not able to receive stimuli because the cells of the epidermis are not living and therefore there are no sensory receptors in the skin.
False; stratum granulosum
T or F: The stratum corneum (outermost layer of skin) is a zone of approximately four layers of viable cells that are able to synthesize proteins that keep the outer layer of skin smooth and soft.
False; extends through entire dermis
T or F: When a patient is said to have "third-degree burns," this indicates that the patient has burns that cover approximately one-third of the body.
False
T or F: When an individual is exposed to extremely low air temperatures, the dermal blood vessels will dilate so that blood and heat will be dissipated.
ceruminous
The ________ gland is a modified sudoriferous gland that secretes wax. A) eccrine B) apocrine C) ceruminous D) mammary
terminal
The coarse hair of the eyebrows and scalp is called ________ hair.
99% water, sodium chloride, trace amounts of wastes, and vitamin C
The composition of the secretions of the eccrine glands is ________. A) primarily uric acid B) 99% water, sodium chloride, trace amounts of wastes, and vitamin C C) fatty substances, proteins, antibodies, and trace amounts of minerals and vitamins D) metabolic wastes
Stratum corneum
The cornfield layer of epidermis that actually protects
Blood Reservoir
The dermal vascular supply can hold up to 5% of body's blood volume.
has two layers
The dermis ________. A) is an avascular connective tissue layer B) has two layers C) lacks sensory corpuscles and glands D) is where melanocytes are found
the reticular layer
The dermis has two major layers; which of the following constitutes 80% of the dermis and is responsible for the tension lines in the skin?
fibroblasts, macrophages, and mast cells
The dermis is a strong, flexible connective tissue layer. Which of the following cell types are likely to be found in the dermis? A) goblet cells, parietal cells, and Kupffer cells B) monocytes, reticulocytes, and osteocytes C) fibroblasts, macrophages, and mast cells D) osteoblasts, osteoclasts, and epithelial cells
They are genetically determined, therefore unique to each person.
The design of a person's epidermal ridges is determined by the manner in which the papillae rest upon the dermal ridges to produce the specific pattern known as handprints, footprints, and fingerprints. Which of the following statements is true regarding these prints or ridges?
four different cell shapes found in five distinct layers, each cell shape with a special function
The epidermis is responsible for protecting the body against invasion of bacteria and other foreign agents primarily because it is composed of ________. A) stratified columnar epithelium B) three layers of keratinized cells only C) four different cell shapes found in five distinct layers, each cell shape with a special function D) a tough layer of connective tissue
allow the hair to assist in touch sensation
The function of the root hair plexus is to ________.
Holocrine secretion
The gland becomes packed with secretory vessels and then bursts, releasing the secretion and destroying the cell
Vitamin D functions as a precursor for __ in the endocrine system.
The hormone calcitrol
macrophages called Langerhans' cells
The integumentary system is protected by the action of cells that arise from bone marrow and migrate to the epidermis. Which of the following cells serve this function? A) cells found in the stratum spinosum B) macrophages called Langerhans' cells C) keratinocytes, because they are so versatile D) Merkel cells
granulosum
The layer of the epidermis immediately under the stratum lucidum in thick skin is the stratum ________.
Stratum basale
The layer that contains the mitotic viable cells of the epidermis.
Sebaceous (Oil) Glands
The most abundant cells of the epidermis. Simple branched alveolar glands that are found all over the body except in the thick skin of palms and soles. . Secrete oily substance called sebum. Most develop from hair follicles. active at puberty.
Keratinocytes
The most abundant cells of the epidermis.Main role is to produce keratin, the fibrous protein that helps give the epidermis its protective properties.
Eccrine Sweat Glands
The most common sweat glands. Widely distributed over the body.Secreting glands, are far more numerous and are abundant on palms, soles of feet and forehead. Each is a simple, coiled, tubular gland. Ducts connect to pores. Sweat: 99% water, NaCl, vitamin C, antibodies, dermcidin and metabolic wastes.
nutrition and hormones
The most important factors influencing hair growth are ________.
Name the Appendages of the Skin
The nails, sweat glands, sebaceous (oil) glands, hair follicles and hair.
Why is Stratum lucidum clear?
The nuclei, organelles, and cell membranes are no longer visible in the cells
Pheromones
The odoriferous secretion of apocrine sweat glands. Acts as sexual attractant.
lucidium
The only place you will find stratum ________ is in the skin that covers the palms, fingertips, and soles of the feet.
Keratin
The protein found in the epidermis that is responsible for toughening the skin.
the major part of its makeup is adipose, which serves as an effective shock absorber
The reason the hypodermis acts as a shock absorber is that ________.
Vitamin D is essential for the levels of what in the body?
The regulation of calcium and phosphate levels
by hormones, especially androgens
The sebaceous glands are simple alveolar glands that secrete a substance known as sebum. The secretion of sebum is stimulated ________. A) by high temperatures B) when the air temperature drops C) by hormones, especially androgens D) as a protective coating when one is swimming
What is the Integumentary System
The skin -- a complex set of organs that covers and protects body.
Stratum spinosum and stratum basale are collectively called _.
The stratum germinativum
Hypodermis (Superficial Fascia)
The subcutaneous tissue deep to the skin. It is not part of the skin, but it shares some of the skins protective functions. It is superficial to the tough connective tissue wrapping (fascia) of the skeletal muscles, consists mostly of adipose tissue. Functions: Anchors the skin to the underlying structures (mostly muscle), acts as a shock absorber.
lunula
The white crescent portion of the nail is called the ________.
Stressors such as acutely high fever, surgery, severe emotional trauma; drugs such as antidepressants and chemotherapy drugs; burns and radiation; and a protein-deficient diet can cause hair loss or thinning.
There are several reasons other than genetics for hair loss. Identify some of these other factors.
What do cutaneous receptors respond to?
Thermal, mechanical (pressure, touch, vibration), and noxious (pain) stimuli.
Layers of the Epidermis
Thick skin which covers the palms, fingertips, and soles of feet; Epidermis consists of 5 layers, or strata (bed sheets); superficial to deep: Stratum Corneum, Stratum Lucidum, Stratum Granulosum, Stratum Spinosum and Stratum Basale. MNEUMONIC: Cora, Luci's Grandma, Spins Baseballs.
Stratum lucidum only exists in _.
Thick skin: epidermis of lips, pans of hands, soles of feet
Papillary Layer
Thin superficial layer is aerolar connective tissue, with fine interlaced mat of loosely woven collegen and elastic fibers. Has superior surface callled dermal papillae.
Skin Color
Three pigments contribute to skin color: melanin, carotene, and hemoglobin.
1) direct damage 2) UV can generate highly reactive molecules that disrupt DNA and proteins 3) UV causes clumping of elastic fibers and breakdown of collagen 4) can suppress immune response
UV Damage
Describe the function of vitamin D production
UV exposure, Vitamin D helps absorb calcium through digestive tract
Rules of Nines
Used to estimate the volume of fluid loss from burns.
What is the primary type of fibers found in reticular layer of dermis?
Very dense, regularly arranged collagenous fibers
Merocrine sweat glands produce perspiration that is more than 99% __.
Water
Lamellated granules of the cells of the stratum granulosum, a glycolipid that is secreted into extracellular spaces.
Water loss through the epidermis could cause a serious threat to health and well-being. Which of the following protects us against excessive water loss through the skin?
What is perspiration composed of?
Water, salts, urea, uric acids- waste products
Name the functions of the integumentary system
Waterproof, cushion, protect the deeper tissues, excrete waste, regulate temperature, provide sensory input and synthesize vitamin D.
1. Protection against abrasion. 2. Protection from the sun's radiation. 3. Involved in the immune system. First line of defense. 4. Protection from water loss. 5. Protection from heat loss. 6. Covers the bodyinterphase with the outside. 7. Sensory perception.
What are six of the functions of the epidermis?
1. Feed and oxygenate the epidermis. 2. Provide touch and pain receptors. 3. Form the underlying foundation for ridges of the hands and toes.
What are the functions of the papillary layer of the skin?
Pale, fine body hair associated with newborn children, women, and bald men.
What are vellus hairs?
Large losses of skin, as with severe burn injuries, allow excessive fluid loss and infection. Skin grafting or "synthetic skin" applications are usually necessary.
What complications might be anticipated from the loss of large areas of skin surfaces?
catastrophic fluid loss
What is the first threat to life from a massive third-degree burn? A) infection B) catastrophic fluid loss C) unbearable pain D) loss of immune function
What is the connection between dehydrocholesterol and vitamin D?
When dehydrocholesterol is synthesized in the digestive system it then can move to the skin and through exposure to ultraviolet light from the sun will be converted to vitamin D
What causes acne?
When sebaceous glands become blocked they may become infected with staf or strep
Meissner's corpuscles
Which of the following cutaneous receptors is specialized for the reception of touch or light pressure? A) Meissner's corpuscles B) Pacinian corpuscles C) free nerve endings D) Krause's end bulbs
Fingernails are a modification of the epidermis.
Which of the following statements best describes what fingernails actually are? A) Fingernails are a modification of the epidermis. B) Fingernails are derived from osseous tissue. C) Fingernails are extensions of the carpal bones. D) Fingernails are a separate tissue from the skin, formed from a different embryonic layer.
Prolonged exposure to the sun induces melanin dispersion, which in turn acts as a natural sunscreen.
Which of the following statements indicates the way in which the body's natural defenses protect the skin from the effects of UV damage?
stratum basale
Which of the followinglayer is responsible for cell division and replacement?
Kinky hair has flat, ribbonlike hair shafts.
Which statement correctly explains why hair appears the way it does? A) Kinky hair has flat, ribbonlike hair shafts. B) Perfectly round hair shafts result in wavy hair. C) Air bubbles in the hair shaft cause straight hair. D) Gray hair is the result of hormonal action altering the chemical composition of melanin.
Good because the sweat and evaporating of the sweat causes cooling of the body. Bad because excessive water and salt loss may occur. Fluid and electrolyte imbalances may follow.
Why is profuse sweating on a hot day good, and yet a potential problem?
The skin proper must retain flexibility to give up excess body heat, so it must not function as a heat barrier. The hypodermis contains adipose which acts as an insulator. With this set up, extra blood (and heat) can be shunted above the hypodermis when heat loss is desirable.
Why is skin not considered a heat barrier for the body?
Carotene
Yellow to orange pigment, that tends to accumulate in the stratum corneum and in fatty tissue of the hypodermis. Its color is most obvious in palms and soles of feet, where stratum corneum is the thickest.
DELETE
Yellowish-orangish pigment not naturally produced by body. Why people and babies who eat carotene rich foods have an orange color
Melanocytes
________ are pigment-producing cells in the epidermis.
Porphyria
________ is an inherited condition that affects the heme pathway; it leaves the skin scarred and gums degenerated, and may have led to the folklore about vampires.
White hair means?
acceleration of air bubbles in shaft
What does the deeper part of the dermis contain?
adipose cells, hair follicles, nerve endings, and oil and sweat glands
What is the inherited inability of an individual to produce melanin?
albinism
What has a musky odor bc its miloky secretion is decomposed by bacteria?
apocrine
What is secreted by hair follicles?
apocrine
What is a programmed cell death in which the nucleus fragments before the cell dies, organelles degenerate, and membrane enclosed granules secrete lipid substance which waterproofs?
apoptitus
What kind of tissue is the subcutaneous layer made of?
areolar and adipose tissue
How does the integumentary system regulate an increase in body temperature?
as body temperature rises, nerve impulses stimulate structures in the skin and other organs to release heat, warmed blood reaches hypothalamus in brain which controls body temperature and signals muscles in walls of dermal blood vessels to dilate allowing more blood to enter them and escape to the outside, simultaneously the nervous system stimulates the eccrine glands to become active and release sweat onto the skin surface, which as evaporates carrying heat away from the surface
What are capillary loops associated with?
blood capillaries
The subcutaneous layer contains a large number of __ to supply skin.
blood vessels
What are the two functions of the dermal layer?
blood vessels nourish stratum basale and dermal cells, and constrict/dilate to help regulate body temperature
What is the base of the follicle called?
bulb
What do dermal papille contain?
capillary loops, corpuscles of touch, messiner corpuscles, and free nerve endings
what are the lesion structural differences between cutaneous carcinomas and cutaneous melanomas?
carcinoma are either flat or raised, usually adhere to skin, slow growing, can be cured completely through surgery or radiation. melanoma have irregular outlines, may feel bumpy, spread horizontally through body, but may invade in the body making treatment difficult
What pigment is yellow-orange and causes the skin to turn orange?
carotene
What gland is found in the external auditory canal?
cebaceous
Which gland provides a sticky barrier against foreign particles?
cebaceous
What occurs in the stratum spinosum?
cells are far enough away from the dermal blood vessels that they begin to compact and die
What is the function of the epidermal layer?
cells in deeper layers are living and dividing that push older cells to the surface where older cells die and fill with keratin to provide tough, waterproof protection
Tell how the dermis is involved in age related changes.
collagen and elastin fibers break down causing wrinkles, macrophages aren't effective, causing a weak immune system, and skin becomes dry because of a decrease in sebaceous glands.
What kind of tissue is the dermis composed of?
connective tissue
What kind of tissue is the dermis made of?
connective tissue
What is the structure of the subcutaneous layer?
connects skin to underlying structures, composed of adipose and loose connective tissue
1) Fluid Loss: must be replaced intravenously immediately can lead to kidney shutdown, circulatory shock 2) Infection: Sepsis is the leading cause of death in burn victims Due to breakdown of skin barrier, and secondary immune suppression Loss of proteins and electrolytes Burn patients need thousands of extra calories for protein replacement and healing Electrolytes must also be carefully regulated
consequences of Severe Burns
What is the difference between cutaneous carcinomas and cutaneous melanomas?
cutaneous carcinomas are caused by regular exposure to sunlight while cutaneous melanoma is cause by short, intermittent exposure to high-intensity sunlight
What is a bluish skin color due to lack of oxygen?
cyanotic
What occurs in the stratum corneum?
dead cells are collected and filled with keratin allowing cells to be tough and offer protection and replace cells worn away by wear and tear
Grey hair means?
decline in synthesis of melanin
What is the thicker, deeper layer of the skin?
dermis
What is the main source of sweat?
eccrine
What is the most common sweat gland that opens as pores on skin?
eccrine
What occurs during the migratory phase of dermal wound healing?
epidermal cells migrate across the wound and blood clots forming scab
What is the superficial, thinner layer of the skin?
epidermis
Where are melanocytes found?
epidermis of the penis, nipples, area around the nipples, face, and limbs
What kind of tissue is the epidermis made of?
epithelial tissue
What is redness of skin caused by engorgement of capillaries, heat, or infection?
erythema
The apocrine gland is more active with?
excitement, fear, and stress
All of the glands are __ in nature which means they use ducts to secrete.
exocrine
What two functions do the collagen and elastin fibers deep in the dermis provide the skin with?
extensibility and elasticity
Which hair protects the eyes from foreign particles?
eyelashes
The subcutaneous layer stores what?
fat
Melanin accumulates in patches to form __, __, and __.
freckles, age spots, and nevus
Which accessory organs regulate body temperature?
glands
Which accessory organs protect?
hair and nails
What is the part of the hair that surrounds the root?
hair follicle
What are the nerve endings surrounding the hair follicle that are sensitive to touch called?
hair root plexuses
What are accessory organs of the skin?
hair, glands, nails
What are the functions of the nail?
help us grasp and manipulate small objects, protect, allow us to scratch
What pigment causes the skin to turn from pink to red ?
hemoglobin
What is a condition of excess body hair caused by excessive androgen?
hirsutism
How is skin color determined?
how much melanin is produced from a melanocyte regulated by DNA
What is another term for the subcutaneous layer?
hypodermis
What causes baldness (alopecia)
infection, emotional stress, drugs, radiation, male hormones
What causes acne?
inflammation of the sebaceous glands
What are the steps in healing a dermal wound?
inflammatory phase, migratory phase, proliferate phase, and maturation phase
What are the three functions of the subcutaneous layer?
insulates, cushions, energy supply
Describe the function of regulation of body temperature
insulating barrier, sweat, blood supply
What is a yellow color due to biliruben in the liver?
jaundice
What kind of cells is the epidermis composed of?
keratinized stratified squamous epithelial
What type of cells produce keratin?
keratinocytes
The epidermis contains 4 main types of cells. What are they?
keratinocytes, melanocytes, langerhans, and merkel
What causes hair to turn white or grey?
lack of pigment in the cortex of a hair shaft, melanin production decreases with age
The subcutaneous layer contains nerve ending called what?
lamellated corpuscles
What type of cells are easily damaged by UV rays?
langerhans
What type of cells participate in the immune response against microbes that invade the skin?
langerhans
What is the main function of eccrine?
maintaining body temperature
What is androgenic alopecia?
male pattern bladness
The bulb contains the __ which produces new hairs by cell division when needed.
matrix
What can range from yellow-red to brown-black and is the pigment for skin color?
melanin
What pigment causes the skin color to vary from pale yellow to red, to tan to black?
melanin
What pigments are found in the skin?
melanin, hemoglobin, carotene
What cell is 8% of the epidermal cells?
melanocytes
What causes variation in hair color?
melanocytes produce different pigments as detailed by the DNA
What type of cells help detect different touch sensations by contacting the flattened process of a sensory neuron tactile disc?
merkel
What are nerve endings that are sensitive to touch?
messiner corpuscles
What occurs in the stratum basale?
mitosis, as cells are pushed to the surface they die due to being cut off from blood supply
How does the integumentary system regulate a decrease in body temperature?
muscles in the walls of dermal blood vessels are stimulated to contract decreasing flow of heat-carrying blood through skin reducing heat loss and sweat glands remain inactive, nervous system stimulates muscles to contract slightly increasing heat through cellular respiration and small muscles may contract rhythmically with great force causing shivering which generates more heat
What are the parts of the nail?
nail body, free edge, nail root, lunula, cuticle
The suderiforous glad is found everywhere except?
nails, lips, ear drum
1st, 2nd, 3rd
name skin burn depth
Skin graft
needed to support regeneration (repair)
What are free nerve endings?
nerve ending that are sensitive to pain, warmth, coolness, tickling, and itching
What is the structure of nerve receptors
nerve ending wrapped with connective tissue
When the sebaceous gland is overactive what kind of skin do you have?
oily skin
What occurs in the stratum granulosum?
older cells develop proteins as they die, precursors to keratin
What are blackheads?
oxidized sebum
What are the different types of nerve receptors?
pacinian corpuscles and meissner corpuscles
What is the difference between pacinian corpuscles and meissner corpuscles?
pacinian respond to changes in deep pressure, while meissner respond to slight pressure changes and fine touch
What is paleness of skin that may occur in shock and anemia?
pallor
The suderiforous glads are most numerous in the?
palms, soles, forehead, axillery region
What are the two regions of the dermis?
papillary region and reticular region
What occurs during the maturation phase of dermal wound healing?
phagocytes remove dead cells, cells mature to heal wound and scab falls off
What is stratum lucidum?
present only on palms and soles, it is 3 to 4 rows, flattened, dead cells containing keratin precursors
What can prolonged and excessive exposure to UV light cause?
prolonged exposure - increased melanin and darker skin means a tan, excessive exposure - sunburn or DNA mutations mean malignant melanoma
What are the functions of the integumentary system?
protection, absorption and secretion, produces vitamin D, regulates body temperature, sensory receptors, and prevents water loss
What are the basic functions of the Integumentary system?
protection, regulation of body temperature, communication, excretion of wastes, and vitamin D production
Describe the function of communication
react to stimuli-cold, hot, touch, pain
What is the function of nerve receptors?
receive information from outside world and send to brain
What occurs during the inflammatory phase of dermal wound healing?
redness (vasodilation), heat (bi-product of metabolic activity), swelling (fluids leave blood vessels into tissues, white blood cells invade), pain (neuron injury and increase in pressure due to swelling)
debrided
removal of burned, dead skin
What is the portion of hair below the skin that penetrates the dermis and subcutaneous layer?
root
Which gland is found everywhere except the palms and soles?
sebaceous
Which gland is located in the dermis and opens into the upper part of the hair follicle?
sebaceous
Which gland is more active during puberty and gets inactive with age?
sebaceous
What is the difference between sebaceous glands and sweat glands?
sebaceous glands contain groups of specialized epithelial cells and are usually associated with hair follicles and secrete an oily mixture of fatty material and cellular debris called sebum which keeps hair and skin soft, pliable, and waterproof, while sweat glands are widespread exocrine glands in the dermis or subcutaneous line with sweat secreting epithelial cells
What substance is produced by sebaceous glands?
sebum
What is the portion of hair above the skin called?
shaft
Hair is fused, dead keratinized cells that consist of a __ and __.
shaft and root
What is the stratum basale?
simple columnar cells capable of mitosis
covers the external surface of the body
skin (cutaneous membrane)
What are the dermal papille?
small fingerlike projections
What information can be gained by doing a scale cast of hair?
species identification
What are the types of skin cancers?
squamous cell carcinoma, basal cell carcinoma, malignant melanoma
What is stratum spinosum?
stratified cuboidal cells that are mainly dead
What are the layers of the epidermis?
stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum
What layer is constantly shedding?
stratum corneum
What layer is the top layer, the thick skin?
stratum corneum
Which layer gets replaced by deeper layers?
stratum corneum
Which layer has callouses?
stratum corneum
Which layer is the deepest layer and is composed of a single layer of cuboidal or columnar keratinocytes?
stratum germanium (basale)
What layer is 3-5 layers of flattened kertainocytes and undergoes apoptitis?
stratum granulosum
Which layer has 3-5 layers of keratinocytes and is found only on the fingertips, palms, and soles?
stratum lucidium
What layer of the epidermis is found only in certain places and what are those places?
stratum lucidium, fingertips, palms, soles
What are the two types of intradermal injections?
subcutaneous injections go into the subcutaneous layer and intramuscular injections go into muscles
What is deep to the dermis and not considered part of the skin?
subcutaneous layer
What stores fat and contains blood vessels and nerve endings?
subcutaneous layer
Which glad is found throughout the body, except in the nails, lips, and eardrum?
suderiforous
group of organs working together to perform specific activities
system
What are corpuscles of touch?
tactile receptors
What happens to cells as they are pushed towards the surface?
the farther cells move, the poorer their nutrient supply becomes and they die
What occurs during the proliferate phase of dermal wound healing?
there is a reestablishment of epidermis and connective tissue below; fibroblasts migrate and form collagenous fibers, binding wound together (sutures speed up)
Dark colored hair means?
true melanin
Blonde and Red hair means?
variants of melanin (sulfur and iron)
Describe the function of protection
vs. body fluid loss, injury, UV light, microorganism
What can the size and shape of a medulla tell us?
what species or race the hair belongs to
What is the structure of the dermal layer?
widely dispersed cells, highly vascular
Body temperature regulation
~500 ml/day of routine insensible perspiration (at normal body temperature). At elevated temperature, dilation of dermal vessels and increased sweat gland activity (sensible perspirations) cool the body.
