Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
|
What is the largest organ in the body? What is it made up of? What are the 5 epidermal derivatives of the skin? |
Integumentary system (15-20% of body mass): Made up of epidermis, the dermis, and the hypodermis Epidermal derivatives of the skin include - Hair follicles and Hair - Sweat Glands - SebaceousGlands - Nails - MammaryGlands |
|
|
What are 6 functions of the integumentary system? |
1.Barrier 2.Immunologic 3.Maintains homeostasis (temp and water loss) 4.Sensory perception (ext. env to the NS) 5.Synthesis of vitamin D 6.Excretion (sweat/sebum) |
|
|
What are examples of thick epidermic skin layer? Thin epidermic layers are found in other region and has? The thickest epidermic layer is found? The top layer of epidermis called the __ is much thicker in thick skin |
Palm and soles of feet have thick epidermic layer Thin is found on other regions and has hair Thickest is on the upper region of the back Epidermis (top) is the stratum cornum and is much thicker in thick skin |
|
|
Epidermis = from Ectoderm
Dermis = from mesoderm |
|
Which layer is most differentiated? What layer is only found in thick skin? Why does the 3rd layer from the top stain darkly? |
Stratum corneum is most differentiated St. Lucidum is only found in skin The St. granulosum is only found in the thick skin |
|
What is the main cell in the epidermis? What are the other 3 types, where are they, and what do they do? |
1. Keratinocyte produces intermediate filament keratin 2. Melanocyte: produce melanin,found in deepest layer of epidermis (st. basale) 3. Merkel cells for tactile sensation (touch) 4. Langerhan's cell in st. spinosum are antigen presenting cell. |
|
|
How does Stratum Basale (St. Germinativum) remain firmly attached to dermis? The keratinocytes are densly packed together and attached to each other by? |
Proteins that make up the hemidesmosomes are attached to the IF (intermediate filaments) or tonofilaments within the keratinocyte Cells are attached to each other laterally by desmosomes |
|
|
Melanocytes (derived from neural crest) can be identified by? They do not form junctions with the keratinocytes but are associated with them by their? They attach to the basal lamina via? Their processes contain melanin that protects from |
Dark elongated nuclei and clear/white cytoplasm Do not form junctions with keratinocytes, but are associated with keratinocytes by processes Hemidesmosmes UV radiation |
|
|
Melanin synnthesis: Oxidation of __ becomes DOPA which becomes melanin When melanin gets to the top of the finger like processes they are donated (cytocrine secretion) to? What does the melanin do for these cells? |
Oxidation of tyrosine becomes DOPA which becomes melanin When they get to the top of the finger like processes they are donated to keratinocyte in st. spinosum and basale They need melanin to protect their nuclei during mitosis (against UV) |
|
|
(melanocytes that grow in clusters form? lack of melanin (tyrosinase) result in? Immune cells destroy melanocytes result in?) |
moles Albinism leukoderma (white patches of skin) |
|
|
Merkel cells associate with keratinocytes via? They contain __ and are associated with unmyelinated nerve fibers They are mechanoreceptors of the epidermis and abundant in? |
Desmosomes Neurosecretory granules Abundant in fingertips |
|
|
In the stratum spinosum, cells at the bottom are more cuboidal and more flattened in the upper They have short spiny processes that hold other cells tightly from? They have more __ that become organized into bundles called? They also have membrane coating granules that contain? They become exocytosed and lie in the intercellular spaces between? This lipid layer does what 3 things? |
In the stratum spinosum, cells at the bottom are more cuboidal and more flattened in the upper. Have short spiny processes that extend from one cell to the next from desmosomes Have more tonofilaments become organized into bundles called tonofibrils Has membrane coating granules that have lipids and proteases Contents becomes exocytosed and lie in the intercelular spaces between st. granulosum and st. corneum This lipid layer contributes to water barrier of skin, maintains body homeostasis, and acts as antibacterial barrier. |
|
|
What are star shaped immune cells in st. spinosum, are mobile, and interact with T cells to present antigens -They are stained with antibody to be identified |
Langerhan cells |
|
|
In the stratum granulosum, there are 2 types of granules. One of them is the membrane coating granule, what does it do? The other is keratohyaline granule which disperses __ in the cytoplasm and joins with __ located within the cell. It contributes to the barrier but also does what? Vitamin D is made in this layer under the influence of? -Cells start losing organelles here |
The membrane coating granule releases lipid into intercellular spaces between cells creating a water barrier Keratohyalinegranule disperses Filagrin in the cytoplasm and joins with tonofilaments located within the cell and contributes to the barrier but also changes the cell to differentiate into the cell found in st. corneum -VitaminD is made under influence of sunlight or diet |
|
|
St. Lucidum (clear translucent layer) is mostly seen in? What structures do they lose? What do they fill in with? |
St. Lucidum Seen in thick skin -lose nuclei and organelles -fill with keratin |
|
|
St. Corneum (outermost layer) Cells have lost nuclei and organelles and filled with keratin filaments (tightly packed tonofilaments) - like st. lucidum They are most differentiated and is coated with? The innerside has? Desmosomes between cells are broken down by? These are activated by __ in the? |
Most differentiated and plasma membrane is coated with lipid (water barrier) Inner side has keratin cross linked with filagrin Proteases breakdown desmosomes Proteases are activated by low pH (acidic regions) in superficial layer of skin - Cells are shed from the skin surface (desquamation) |
|
|
Epidermis-dermis junction There are projections of epidermis going downward into the dermis called? Dermis projections going upward upward into the epidermis is called? -result in thick ridges for? |
Epidermis-dermis junction Rete ridges dermis papilla Result in thick ridges for fingerprints, allowing for gripping surfaces |
|
|
The dermis has 2 layers: Which one is -thinner -has contains loose CT -type I and III colagen -elastic fibers -capillaries and nerves? Which one is -thicker -has dense irregular CT (langers lines) -Type I collagen -elastic fibers -blood vessels/lymphatics/nerves -smooth and skeletal muscle? It's responsible for what 2 things due to collagen and elastic fibers? Also provides sensory perception, nutrients, carriesaway from the keratinocytes via blood, and thermoregulation What 2 components are important for maintaining the structure of CT? |
The dermis has 2 layers
1. Papillary Dermis 2. Reticulardermis Responsiblefor mechanical strength and elasticity -Copper and vitamin C |
|
What is the subcutaneous layer, deep to the reticular layer that links the skin to underlying muscle?
Contains loose irregular CT (with BV) tissue and __ - Also contains ducts and secretory portions of sweat glands, hair follicles, nerves -Provides insulation and has a thin layer of skeletal muscle for facial expression and smooth muscle cells of the arrector pili muscle (goose bumps) |
Hypodermis Adipose tissue |
|
|
Sensory receptors in the skin: Which is the most frequent in the epidermis and terminate in the stratum granulosum? -Also responds to pain and temperature Which ispresent in the stratum basale of the epidermis and is associatedwith an afferent fiber? |
Free nerve endings Merkel disc |
|
|
Encapsulated nerve ending that sits in the papillary layer of the dermis? -responsible for light touch/detects shape and texture -Made up of unmeylinated nerve fiber but still associated with schwan cells around the axon |
Meissner's corpuscle |
|
|
Encapculated nerve ending that are large ovoidstructures found in the deep layers of the dermis and hypodermis (like an onioncross section)? - loses its myelination and continuesto be covered by schwan cells - Senses pressure and vibration on surfaceof the skin due to displacement of lamellae Ruffini's corpuscle is sensitive to? |
Ruffini = stretch and torque |
|
|
Epidermal derivatives of the skin: Hair follicle Epidermis invaginates into the dermis and form outer sheaths of hair follicle - At the base of the hair follicle is an invagination with highly vascularized CT called the? Matrix cells adjacent to the above form a __ that contributes to hair growth and house melanocytes In the lining of the follicular canal are __ that contribute to hair follicle and sebaceous glands and participate in wound healing |
Dermal papilla Germinative layer Epidermal stem cells |
|
|
Epidermal derivatives of skin: Sebaceous gland - Secretes fatty product called __ that coats hair and skin surface -Closely associated with it is the arrector pili muscle -Develops from external root sheath of hair follicle and secrete by holocrine secretion (cell is lost in the secretory process) -Located in the __ typically associated with the hair follicle -The excretory duct opens in the neck of the hair follicle |
Sebum - lubricates and prevents dryness Dermis |
|
|
- A band of smooth muscle attached from the papillary layer of the dermis to the dermal root sheath of the hair follicle trapping the sebaceous gland in between is called? - Squeezes sebum from sebaceous gland and contraction causes goose bumps |
Arrector pili muscle |
|
|
Epidermal derivatives of skin: What are simple coiled tubular glands that extend from hypodermis to the epidermis? |
Sweat gland |
|
|
SweatGlands: Which sweat gland is over entire body except lips andexternal genitalia - Notassociated with a hair follicle - Downgrowth of the epidermis - Simpletubular gland with ductInvolvedin thermoregulation - Respondto heat and stress - Sweat:urea, NaCl,uric acid, ammonia - Ducts:some resorption to create a hypotonic sweat |
Eccrine Sweat gland - Have surrounding myoepithelial cells - Secrete by exocytosis from granules (merocrine) |
|
|
Sweat glands: - axilla,areola, nipple, anus, external genitalia - Downgrowth of epidermis - Coiled,tubular branched glands - Associatedwith hair follicle - Secretionenters follicle at the level of the sebaceous gland - Secretorygranules discharged by exocytosis - Proteinrich secretion containing pheromones (no resorption in ducts) - Functionalat puberty - Dependenton sex hormones - Respondto emotional and sensory stimuli |
Apocrine Sweat gland |
|
|
The sweat gland has a long and coiled excretory duct The portion of the duct lying in the dermis is lined by stratified cuboidal epitheliums that reabsorb? Patients with __ results in decreased reabsorption of ions and causes high salt content in sweat |
Na+ and Cl- and water under influence of aldosterone Cystic fibrosis |
|
|
Sweat glands play a role in maintaining? NumerousBV in loose areolar CT - Branchesof the hypodermic and cultaneousplexus nourishes the adipose tissue of hypodermis, sweat glands and the hairfollicles |
normal body temperature |
|
|
The nails are hard keratin plates Nail bed consist of? Eponychium makes up the? -contributes to formation of the cuticle Hyponychium represents? |
Epidermis and dermis superficial layer of the nail plate The union between the nail and nail plate at the finger tip |
