Chapter 5 anatomy and physiology
strata of epithelium from superficial to deep
TOP to Bottom.; corneum, lucidum, granulosum, spinosum, basale.
Explain how the integument is considered an organ.
The integument is composed of all the tissue types that function in concert to protect the bodies internal organs.
Identify and describe the tissue types that form the subcutaneous layer.
aereolar and dense connective tissues.
What kind of tissue is the epidermis?
keratinized stratified squamous epithelium with no blood vessels and few nerve endings.
the most abundant cell type in the epidermis. Their name is derived from their synthesis of keratin, a protein that strengthens the epidermis considerably. .These gives skin its strength and makes the epidermis water resistant.
keratinocytes
What cells make up the epidermis?
keratinocytes, melanocytes, dendritic cells, tactile cells, and stem cells
what cells make up the stratum basale
keratinocytes, melanocytes, tactile cells.
The first three strata listed are composed of ______ _____ whereas the most superficial two strata contain ______ ______.
living keratinocytes; dead keratinocytes.
scattered among the stratum basale only, They produce and store the pigment melanin in response to ultraviolet light exposure. Branched processes
melanocytes
The deepest epidermal layer is the ____ ______, also known as the stratum germinativum, or basal layer.
stratum basale
What strata of the basale is thick skin found?
stratum lucidum
clear layer, is a thin, translucent region of about two to three keratinocyte layers; found only in thick skin
stratum lucidum
Numerous desmosomes and cell shrinkage produces spiny appearance; Consists of several layers of keratinocytes that produce pre-keratin filaments which causes cell to flatten
stratum spinosum
-Deep to the integument -hypodermis, or superficial fascia. -This layer consists of both areolar connective tissue and adipose connective tissue
subcutaneous layer
what are the functions of the subcutaneous layer
pads and protects the body, acts as an energy reservoir, and provides thermal insulation. Drugs often are injected
These are sensitive to touch and, when compressed, they release chemicals that stimulate sensory nerve endings, providing information about objects touching the skin. In basal layer of epidermis
tactile cells
superficial region of the dermis that is deep to the epidermis Thin zone of areolar tissue in and near the dermal papilla -Allows mobility of white blood cells -Rich in small blood vessels
the papillary layer
the dermis has two layers called
the papillary layer and the reticular layer
deeper and much thicker layer of dermis -Dense irregular connective tissue -Stretch marks (striae): tears in the collagen fibers caused by stretching of the skin -Tension lines/Lines of cleavage
the reticular layer
Fibrosis
the thickening and scarring of connective tissue, usually as a result of injury.
no hair follicles or sebaceous glands
thick skin
Has hair, sebaceous glands, and sweat glands
thin skin
Identify and describe the subcutaneous layer (hypodermis, superficial fascia)
Deep to the integument is a layer of areolar and adipose connective tissue called the subcutaneous layer, or hypodermis.
upward fingerlike extensions of the dermis, friction ridges
Dermal papillae
Identify and describe the layers of the integument (skin). Which layer is superior?
It is composed of two distinct layers: the dermis and epidermis. The dermis is deep to the epidermis.
A single layer of cuboidal to low columnar stem cells and keratinocytes resting on the basement membrane
Stratum basale or germinativum
what cells make up the stratum spinosum?
Several layers of polygonal keratinocytes and epidermal dendritic cells.
horny layer (up to 30 layers of dead, scaly, keratinized cells)
Stratum Corneum
what kind of tissue is the dermis?
both areolar and dense irregular connective tissue
epithelium strata from deep to superficial
bottom to top: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum , and stratum corneum
Repair and regeneration of integumentary system
damaged tissue is replaced only 2 ways, regeneration or fibrosis
Describe the structure and function of hair.
has 3 regions, bulb, root, and shaft
what are epidermal dendritic cells?
immune cells that help fight infection in the epidermis
Functions of integumentary system and again of skin
protection prevention of water loss and water gain metabolic regulation thru vit D secretion and absorption temp regulation immune function sensory reception
Regeneration
replacement of destroyed tissue by the same kind of cells
Is the epidermis keratinized?
yes