MIDTERM 02 - Integumentary System Flashcards
The largest organ of the body
Skin
Forms a physical barrier between the external environment and the internal environment that it serves to protect and maintain
Integumentary system
2 major tissue layers of the skin
Epidermis, Dermis
Superficial layer of the skin; is avascular and contains stratified squamous epithelium
Epidermis
Dense connective tissue; is vascular and is on average, 10 to 20 times thicker than the epidermis
Dermis
Deepest layer of the epidermis that lies next to the dermis; where cells undergoing mitosis can be found
Stratum basale/Stratum germinativum
Is several cell layers thick; contains a weblike system of intermediate filaments
Stratum spinosum/Pricky layer
Is four to six layers thick and accumulates 2 types of granules
Stratum granulosum/Granular layer
2 types of granules in stratum granulosum/granular layer
Keratohyaline granules/Lamellar granules
Helps to form keratin in the upper layer
Keratohyaline granules
Contains water-resistant glycolipid for slowing water loss across the epidermis
Lamellar granules
Formed from dead cells of the deeper strata; occurs only in thick, hairless skin of the palms of hands and soles of feet
Stratum lucidum/Clear layer
Outermost layer of epidermis/shingle-like dead cells are filled with keratin
Stratum corneum/Horny layer
Excessive sloughing of stratum corneum cells from the surface of the scalp
Dandruff
In skin subjected to friction, the number of layers in the stratum corneum greatly increases, producing a thickened area called a __________
Callus/hard skin
Over a bony prominence, the stratum corneum can thicken to form a cone-shaped structure called a __________
Corn
4 cells that can be found in the epidermis
Keratinocytes, Melanocytes, Langerhans cells, Merkel cells
Produces keratin; arises in the stratum basale
Keratinocytes
A fibrous protein that helps give the epidermis its protective properties
Keratin
Spider shaped epithelial cells that synthesize melanin pigment
Melanocytes
Arises from bone marrow and migrate to the epidermis
Langerhans cells
Present at the epidermal-dermal junction; functions as sensory receptor for touch
Merkel cells
2 layers of the dermis
Papillary layer, Reticular layer
Upper dermal region that has areolar connective tissue
Papillary layer
Projections called __________ are present in the papillary layer
Dermal papillae
Papillary layer also house pain receptors and touch receptors called __________
Meissner’s corpuscles
Comprises 80% of the thickness of the dermis; contains dense fibrous connective tissue
Reticular layer
Is important to the surgeon
Cleavage/tension lines
Dermal folds that occur at or near joints
Flexure lines
Polymer made of tyrosine amino acids
Melanin
Yellow to red melanin
Pheomelanin
Brown to black melanin
Eumelanin
Precursor of vitamin A needed for vision
Carotene
Red coloring from blood cells in dermal capillaries
Hemoglobin
Where the skin appear bluish
Cyanotic
Due to embarrassment, inflammation, hypertension, fever, or allergy
Redness/erythema
Due to emotional stress such as fear, anemia, low blood pressure, or impaired blood flow to an area
Pallor/blanching
Occurs when too much bilirubin builds up in the body
Jaundice/yellowing
Example includes vitiligo, which is a skin condition
Depigmentation
Examples includes Addison’s disease and primary adrenal insufficiency
Bronzing/hyperpigmentation
Involves partial or complete absence of melanin; example includes genetic disorder
Albinism
Example includes hematomas
Bruises
Produces oil (sebum), accumulated lipids, and cell fragments which serves as lubricant for skin
Oil/sebaceous glands
Accumulated sebum blocks a sebaceous gland duct
Whitehead
Material oxidizes and dries
Blackhead
An active inflammation of sebaceous glands accompanied by pimples
Acne
Overactive sebaceous gland; also known as ‘cradle cap’ in infants
Seborrhea
Produces sweat; is widely distributed in skin
Sweat/sudoriferous glands
2 types of sweat glands
Eccrine, Apocrine
Produces clear sweat; open to pores on skin surface
Eccrine/merocrine sweat glands
Releases milky/yellowish sweat that also contains fatty acids and proteins
Aprocrine sweat glands
Gland that is found in the eyelids
Ciliary glands
Modified apocrine glands found in the lining of the external ear canal; produces cerumen or earwax
Ceruminous glands
Gland that secretes milk
Mammary glands
Produced by hair follicle
Hair/pili
Dermal and epidermal sheath surrounding hair root
Hair follicle
Smooth muscle cells that pulls hair upright when cold or frightened
Arrector pili muscle
3 types of hair growth
Lanugo, Vellus hair, Terminal hair
Excessive hairiness that may result from an adrenal gland or ovarian tumor
Hirsutism
Hair thinning and some degree of baldness
Alopecia
Most common example includes male pattern baldness
True or frank baldness
Scale like modifications of the epidermis that is heavily keratinized
Nails
Acts as a biomolecular barrier that disrupts bacterial membranes
Antimicrobial peptides (AMPs)
The removal of waste products from the body
Excretion
2 ways on how tissue repair/wound healing occurs
Regeneration, Fibrosis
Replacement of destroyed tissue by the same kind of cells
Regeneration
Repair by dense connective tissue
Fibrosis
Refers to the growth of new capillaries
Angiogenesis
Results when bacteria infecting the throat releases a toxin into the blood that causes a reddish rash on the skin
Scarlet fever
In this condition, the skin produces excess keratin and assumes a characteristic sandpaper texture
Vitamin A deficiency
In this condition, the nails loose their normal contour and become flat or concave
Iron-deficiency anemia
Results in high levels of lead in the hair
Lead poisoning
Is an injury to a tissue caused by heat, cold, friction, chemicals, electricity, or radiation
Burn
Where the part of the stratum basale remains viable, and regeneration of the epidermis occurs from within the burn area
Partial-thickness burns
Involve only the epidermis and are red and painful
First degree burns
Damages both the epidermis and the dermis
Second degree burns
The epidermis and the dermis are completely destroyed, and recovery occurs from the edges of the burn wound
Third degree burns
Are extremely severe burns that affect tissues deeper than the subcutaneous tissue
Fourth degree burns
A general term for different integumentary carcinomas
Skin cancer
The most frequent type; begins with cells in the stratum basale and extends into the dermis to produce an open ulcer
Basal cell carcinoma
Develops from cells immediately superficial to the stratum basale
Squamous cell carcinoma
Is a rare form of skin cancer than arises from melanocytes, usually in a preexisting mole
Malignant melanoma
Is an aggregation, or “nest” of melanocytes
Mole
