Integumentary System & Wound and tissue repair Flashcards
What are the organs of the integumentary system?
Skin, hair, nails and glands
What is the epidermis?
- Outermost layer of the skin (top layer)
- Acts as a protective barrier
- Makes new skin
- Protects body
- Provides skin colour (contains melanin)
What is melanin?
It is a pigment that protects against damage by ultraviolet radiation - determines the colour of your skin
What is another name for the subcutaneous layer?
Hypodermis
What are the 3 major cells that make up the epidermis?
Keratinocytes - produce protein keratin
Melanocytes - skin pigment known as melanin
Langerhan cells - prevent things from getting into skin
What is the dermis?
The middle layer - composed of connective tissue containing collagen and elastic fibres
What epidermal cell has a role in immunity and disease resistance?
Langerhans cells
What layer of epidermis is composed of a single row of cuboidal or columnar keratinocytes?
Stratum basale
What is the dermis?
Middle layer of skin. It’s tole is to support and protect the skin and deeper layers & assist in thermoregulation
What does thermoregulation mean?
Homeostatic process that maintains a seated internal body temp despite changes in external conditions
Where is the stratum lucidum present in?
Only present in thick skin
Constant exposure of skin to friction stimulates the formation of a callus which is the thickening of the … of the epidermis?
Stratum corneum
What layer of the skin is composed mainly of dense irregular connective tissue containing collagen and elastic fibres?
The dermis
Which of the following structures found in the skin plays an important role in thermoregulation?
Sweat glands
In this type of scar the scar tissue extends beyond the boundary of the injury into normal tissue?
Keloid scar
What condition is characterised by excessive body hair caused by tumours in adrenal glands, testes or ovaries?
Hirsutism
Which condition is due to a buildup of bilirubin pigment in the skin?
Jaundice
What term refers to redness of the skin such as seen in pts with inflammation, infection or heat exposure?
Erythema
Which term refers to planes of the skin such as seen in its with shock or anemia?
Pallor
Which term refers to an inflammation of the skin characterised by patches of redness, blistering and extreme itching?
Eczema
A pt has stepped on a nail - list the sequential layers of strata of the epidermis that the nail penetrated through to finally reach the dermis?
corneum, lucidum, granulosom, spinosum, basale
What skin disorder involves inflammation of sebaceous glands by bacteria which thrive in the lipid rich sebum?
Acne
What structures found in the skin help prevent water loss and inhibits bacterial growth on the surface of the skin?
Oil glands
Where are the ceruminous glands located and what do they do?
Located in ear canal and are involved in producing a waxy secretion called cerumen which provides a sticky barrier that prevents entry of foreign bodies into air canal
What is the stratum basale and what does it have ?
Deepest layer of skin
Has keratinocytes stem cells
Contains melanocytes
What are melanocytes
Responsible for producing melanin - which provides the pigment of epidermis and absorbs harmful UV rays and protects cells form the sun.
What are keratinocyte stem cells?
produces protein keratin which helps form hair, nails and skins outer layer
What is the stratum granulosum?
this layer mainly consists of keratinocytes held together by sticky protein. this layer helps make the skin flexible and strong
What are the sticky proteins called that hold together the keratinocytes in the stratum spinosum?
Desmosomes
What is the stratum granulosum layer?
Keratinocytes migrating from the underlying stratum spinosum become known as granular cells in this layer
What is the stratum lucidem?
Thin transparent layer of keratinocytes which become less round and have flatter shape
What are dead keratinocytes called?
Corneocytes = strong dead (keratinocytes) which protect us from harm incl = abrasions, light, heat and pathogens.
What is the stratum corneum?
Top layer of epidermis - keratinocytes become corneocytes
What are merle cells?
Found in the epidermis but usually they exist in the bottom layer i.e. the Basale layer. They are close to nerve endings that receive the same sensation of touch.
What are langerhan cells?
Found in the epidermis, and they prevent things from getting into our skin
What are the two layers of the dermis called?
Reticular dermis
Papillary dermis
What is the reticular dermis?
Bottom layer of dermis, thick, contains blood vessels consists of dense irregular connective tissues containing collagen and elastic fibres.
What is the Papillary dermis?
Much thinner consists of areolar connective tissue containing thin collagen and elastic fibres.
What are sebaceous glands?
Organ in skin that make and secrete sebum. Sebum is a substance that provides a protective coating for skin to help retain moisture – most of these glands connect to hair follicles.
What are sweat glands? (name specific one)
Apocrine glands make thick sticky sweat and are moistly located in armpits and genital areas. These specific sweat glands make us swear when we’re feeling strong emotions like stress.
What are ceruminous glands?
Works together with sebaceous glands in ear canal to make ear wax (only found in outer ear) - ear wax prevents entry of foreign bodies into air canal
Why can skin regenerate at any age?
Because of the presence of stem cells in both epithelial and connective tissue
What is the healing process like for an incision?
More faster
What is the healing process like for an abrasion/laceration?
More slow healing
What is stage 1 one skin repair?
Damage occurs extending through epidermis and dermis = bleeding will occur
What is stage 2 of skin repair?
Blood will clot which restricts entry of additional unwanted micro organisms
What happens in stage 3 of skin repair?
Growth and re building = blood cells including oxygen rich BC arrive to help build new tissue chemical signals tell the cells to create collagen.
What happens in stage four of skin repairr?
loss of scab – fibroblasts continue to migrate and divide in the dermis to create scar tissue
What is a keloid?
Too much collagen is produced in and around scar tissue – what is known as a keloid scar can form. This can be causes by any sort of skin injury one of the most common is it being caused by a body piercing
