Structure and Function of Skin Flashcards
functions of the skin
- barrier function
- immunologic function
- temperature regulation
- protection from radiation
- nerve sensation
- injury repair
- appearance
the skin provides a physical barrier that regulates ____ loss
- water loss
what chronic skin condition is associated with barrier dysfunction
- atopic dermatitis
dysfunction of the immunologic barrier of the skin leads to
- infection
- skin cancer
- inflammatory skin conditions
- allergy
the skin helps maintain a constant body temperature with the insulating properties of ___ and _____
- fat and hair
the skin accelerates heat loss with _____ production and a dense superficial ______
- sweat production
- microvasculature
an example of thermoregulation dysfunction where there are chronic episodic attacks of digital ischemia provoked by exposure to cold is
- Raynaud’s phenomenon
the dark pigment ________ protects cells against ultraviolet radiation
what layer of the skin is it in
- melanin
- epidermis
dysfunction of _______ production causes the patient to be more susceptible to skin cancer
- melanin production
what is pruritus
- itching
what is dyesthesia
- abnormal sensation
4 phases of cutaneous wound repair process
- coagulation
- inflammatory
- proliferative-migratory (tissue formation)
- remodeling
loss of the ability to repair injury leads to
- delayed wound healing
3 layers of the skin
- epidermis
- dermis
- subcutis
what layer of the skin is the topmost layer
consists primarily of
- epidermis
- keratinocytes
what layer lies below the epidermis
consists primarily of
- dermis
- fibroblasts
- collagen
- elastic fibers
other names for the subcutis
- panniculus
- hypodermis
4 major layers of the epidermis (from outside to inside)
- stratum corneum
- stratum granulosum
- stratum spinosum
- stratum basale
it takes how long for basal cells to reach the stratum corneum
it takes how long for cells to shed
- 2 weeks
- 2 weeks
the basal layer is the source of _____ cells
what occurs here
- epidermal stem cells
- cell division
________ (cells) start in the basal layer and move upwards
- keratinocytes
what is the most common form of skin cancer
- basal cell carcinoma
what presents as pearly, erythematous papules or plaques with rolled border and telangectasias in sun-exposed areas
- basal cell carcinoma
spinous layer is the center of the epidermis that has a ________ appearance due to _______ which hold keratinocytes together
- shiny appearance
- desmosomal junctions
______ produced by the keratinocytes in the ____ cell layer and secreted into the extracellular space between the keratinocyte forms a _____ barrier that keeps water in the skin
- lipids
- granular
- water barrier
which layer is made up of desquamating keratinocytes
- stratum corneum
(stratum corneum) thick outer layers of flattened keratizined non-nucleated cells provide a _____ against __________
- barrier
- against trauma and infection
what are keratinocytes in the stratum corneum filled with
- keratin
- filaggrin
what in the stratum corneum surrounds the keratinocytes and provides the water barrier
- lipid mixture
filaggrin is found in what layer of the epidermis
function
- granular cell layer
- retains water within keratinocytes
mutations in filaggrin cause
- atopic dermatitis
what disease is caused by loss of adhesion between the dermis and epidermal layers
- autoimmune blistering disease with autoantibodies to antigens on hemidesmosomes that anchor basal layer to the dermis
- bullous pemphigoid
in _______ the rate of epidermal turnover is increased which leads to cell thickening
- psoriasis
the accelerated rate of movement through the epidermis doesn’t allow adequate time for _______ which is recognized as _______
- differentiation
- scale
three main types of cells that make up the epidermis
which makes up the majority of cells in the epidermis
- keratinocytes (majority)
- melanocytes
- langerhans cells
what holds keratinocytes together and looks like stripes or spines between cells
- desmosomes
melanocytes produce and transfer _____ to the _______ in the _____ layer
- melanin pigement
- to the keratinocytes
- in the basal layer
what are benign collection of melanocytes
- melanocytic nevi
what is a malignancy of melanocytes
- melanoma
what the immune cell of the skin
what kind of cell are they
function
- langerhans cell
- dendritic cell
- present antigen
langerhans cells of the skin are important in ____ type hypersensitivity
- delayed-type
a common skin disease in which langerhans cells play a prominent role is
- allergic contact dermatitis
two layers of the dermis
- papillary dermis
- reticular dermis
what layer of the skin provides a flexible but tough support structure and contains the blood and lymphatic vessels and nerves which supply the skin as well as sweat glands and hair follices
- dermis
what layer of the skin are hair follicles and sebaceous (oil) glands found
- dermis
where do fibroblasts and mast cells reside
- dermis
which cells are responsible for the synthesis and degradation of connective tissue proteins
they are instrumental in
- fibroblasts
- wound healing and scarring
what results from uncontrolled synthesis and excessive deposition of collagen at sites of prior dermis injury and wound repair
- keloids
mast cells are specialized cells that are responsible for the ______ type hypersensitivity reaction in the skin
- immediate type
the mast cell is the major effector cell in _____ which is a vascular reaction of the skin characterized by wheals surrounded by a red halo or flare
- urticaria
_______ is the fat layer which separates the dermis from deeper underlying structures such as fascia and muscle
- subcutis
________ insulates the body, serves as an energy supply, cushions and protects the skin, and allows for its mobility over underlying structures
- subcutis
what is a disorder of the subcutis
classically appears as deep-seated erythematous nodules typically on the ______-
- erythema nodosum
- typically on the shins
another name for inflammation of the subcutis
- panniculitis
adnexal structures include
- pilosebaceous unit
- eccrine gland
pilosebaceous unit consists of
- hair follicle
- sebaceous (oil) gland
- apocrine sweat glands
- arrestor pili muscle
apocrine glands are found where
- axillary and anogenital areas
what is a disorder of the pilosebaceous unit
- acne vulgaris
which glands involve the hair follicle
which do not
- apocrine glands involve hair follicle
- eccrine glands do not
which glands open directly onto the skin surface and are present throughout the body
- eccrine glands
when eccrine glands are genetically absent the patient is exposed to
- hyperthermia
