Chapter 5- The Integumentary System Flashcards
What is the epidermis
The epithelium covering the surface of the skin
What is apocrine glands
A mode of secretion in which the grandular cell sheds portions of its cytoplasm
What is melanin
The yellow- brown pigment produced produced by the melanocytes of the skin
What is the sebaceous glands
Glands that secret sebum; normally associated with hair follicles
What is ceruminous glands
Integumentary glands that secrete cerumen
What is arrector pili
Smooth muscles whose contractions force hairs to stand erect
What is keratin
The tough fibrous protein component of nails, hair, calluses, and the general Integumentary surface
What is inflammation
A nonspecific defense mechanism that operates at the tissue level. Characterized by swelling, redness, heat pain, and sometimes loss of function
What is hair
A keratinous strand produced by epithelial cells of the hair follicle
What is plexus?
A network or braid
What is melanocytes
A specialized cell in the deeper layers of the stratified squamous epithelium of the skin; responsible for the production of melanin
What is the dermis
The connective tissue layer beneath the epidermis of the skin
What is merocrine
A method of secretion in which the cell ejects materials from secretory vesicles through exocytosis
What is sebum
A waxy secretion that coats the surfaces of hair
What is a nail
A keratinous structure produced by epithelial cells of the nail root
What is hypodermis
The layer of loose connective tissue below the dermis; also called subcutaneous layer of superficial fascia
What is scar tissue?
The thick, collagenous tissue that forms at an injury site
What are the 5 layers of the epidermis
- Stratum Corneum
- Stratum Lucidium
- Stratum Granulosum
- Stratum Spinosum
- Stratum Basale
What does thin skin cover?
Almost all of the body
What does thick skin cover?
Palms and soles of feet
What is dermal papillae
It increases the area of the basement membrane
What does the Basale layer do?
Strengthens the attachment between epidermis and dermis
What are Merkel Cells
In the Basale layer, found on hairless skin, and responds to touch
What are melanocytes
It contains the pigment melanin and is scattered throughout the Basale layer
What does the Spinosum layer do?
It keeps diving increasing the thickness
What does the Granulosum layer do?
Stops dividing, produces protein fibers, and create tightly interlocked layer of Keratin surrounded by Keratohyalin
What is the Lucidium layer?
It is clear, found only in thick skin, and covers the Granulosum layer.
What is the corneum layer?
Exposed skin, sheds every two weeks, water resistant
What is carotene?
Orange-yellow pigment found in orange vegetables
What is cyanosis
A severe reduction in blood flow or oxygenation
What are the functions of the Integumentary system?
Physical protection for environmental hazards, storage of lipids, coordination of immune response to pathogens and cancers in skin.
What is the function of the epidermis?
Protects the dermis, prevents water loss and the entry of pathogens, and synthesis of vitamin D3. Sensory receptors detect touch, pressure, pain, and temperature.
What is the function of the dermis?
Papillary Layer- nourishes and supports epidermis.
Reticular Layer- has sensory receptors that detect touch, pressure, pain, vibration, and temperature. Blood vessels assist in thermoregulation.
What are the 5 layers of the Epidermis?
- Stratum Corneum
- Stratum Lucidium
- Stratum Granulosum
- Stratum Spinosum
- Stratum Basale
What are the characteristics of the Basale layer?
Attached to the basement membrane by hemidesmosomes
Forms a strong bond between the epidermis and dermis
What is Dermal Papillae?
It is in the Basale layer. Is increases the area of the basement membrane. Also strengthens the attachment between epidermis and dermis
What are epidermal ridges?
They extend into the dermis and are adjacent to dermal projections- dermal papillae. It helps increase the basement membrane surface area.
What are some characteristics of Stratum Spinosum
Produced by the division of stratum Basale
8-10 layers of keratinocytes bound by desomosomes
Cells shrink until cytoskeleton s stick out
Continue to divide, increasing the thickness
Contain dendritic cells, active in immune response
What are some characteristics of Stratum Granulosum
Stops dividing and starts producing keratin and keratohyalin
What are some characteristics of Stratum Lucidium?
Found only in thick skin
Covers stratum Granulosum
What are some characteristics of Stratum Corneum?
15-30 layers of keratinized cells, water resistant, shed and replaced every two weeks, exposed surface of skin
What is insensible perspiration?
Interstitial fluid lost by evaporation through the Stratum Corneum
What is sensible perspiration?
Water excreted by sweat glands.
What are the results of dehydration ?
Form damage to Stratum Corneum from immersion in hypertonic solution
What does hydration cause?
Results from immersion in hypotonic solution
Causes swelling of epithelial cells, evident on the palms and soles.
What are some factors that determine skin color?
Melanin- yellow- brown or black. Produce by melanocytes in Stratum Basale. Stored in transport vesicles. Transferred to Keratinocytes.
It depend on melanin production, not number of melanocytes.
Also oxygenated red blood cells.
How does skin respond to injury?
Bleeding, inflammation by mast cells, a scab forms to protect the area, germative cells migrate around the wound, macrophages clean the area, fibroblasts and endothelial cells move in producing granulation tissue and produce scar tissue and strengthens the scar tissue.
What is sebaceous glands?
They are a Holocene gland that discharge an oily lipid into a hair follicle.
What is the function of apocrine sweat glands?
Found in armpits, around milled, and groin
Secretes products into hair follicles
Produce cloudy sticky secretions that break down and causes an odor
What is the function of merocrine sweat gland?
Cools skin, excreted water & elctrolytes. Flushes microorganisms and harmful chemicals from skin
What is the function of hair?
Found deep in the dermis.
Protects you scalp from UV radiation, cushion light impacts on the head and insulate the skull.
Hair in your nostrils and ears keep our insects and foreign particles. Same with eye lashes.
Eye brows keep sweat out of the eyes.
What are the functions of nails?
Made deep in the epidermal fold near the bone. Protects the exposed dorsal surface of the tips of the fingers and toes. Also help limit distortion of digits from mechanical stress.
