AP 100, Chapter 4
Epidermis
*stratified squamous epithelium that is capable of keratinizing or becoming hard and tough *composed of up to five layers, or strata *from inside out layers are: stratum basale, spinosum, granulosum, lucidum, and corneum *is Avascular, has no blood supply of its own.
Which of these statements describes the papillary layer of the skin?
Dermal papillary contain papillae loops to nourish the epidermis
Serous Membrane (serosa)
composed of a layer of simple squamos epithelium resting on a thin layer of areolar connective tissue, it lines body cavities closed to the exterior (except dorsal and joint cavities), occur in pairs, fused to the cavity wall parietal layer lines portion of wall of ventral cavity and folds in on itself to form the visceral layer that clings to organs
Which effect of aging is accelerated by smoking and sun exposure?
loss of skin elasticity
Pericardium
serosa lining the heart in thorax, isolating it from the lungs
Acne is an infection of the __________ glands.
sebaceous
Merkel cells
epidermal-dermal junction associated with sensory nerve endings and serve as touch receptors
Peritoneum
serosa lining the abdominal cavity and covering its organs
Pleura
serosa lining the lungs in the thorax, isolating it from the heart
What pigment found in skin originates from outside the body?
carotene
Mucous Membrane (mucosa)
composed of epithelium resting on loose connective tissue membrane called lamina propia, this membrane type lines all body caviites open to exterior such as hollow organs of the respiratory, digestive, urinary, and reproductive tracts, name refers to location, not cellular makeup which varies but usually containes either stratified squamos epithelium (mouth and esophagus) or simple columnar epithelium (digestive tract), always wet membranes bathed in secretions, adapted for absorption or secretions as most do though not all (respiratory and digestive secrete protive mucus while urinary does not)
Synovial Membranes
composed of soft areolar connective tissue and contain no epithelial cells, they line the fibrous capsules surrounding joints where they provide a smooth surface a secrete a lubricating fluid as well as lining small sacs of connective tissue called bursae and the tube-like tendon sheaths, both cushion organs from moving against each other during muscle activity (tendon across bone surface)
What causes hair to stand up and the skin to dimple when one is cold or frightened?
contraction of arrector pili muscles
Body Membranes
cover surfaces, line body cavities, and form protective/lubricative sheets around organs they fall into two major groups; epithelial membranes (cutaneous, mucous, serous) and connective tissue membranes (synovial)
Epithelial Membranes
covering and lining membranes, including the cutaneous membrane or skin, the mucous membranes, and the serous membranes however while all do contain an epithelial sheet, it is always combined with and underlying layer of conective tissue so really they are simple organs
Integumentary System
cutaneous membrane and its derivatives of the sweat and oil glands, the hair and nails, together serve a number of functions mostly protective
Mountain climbers frequently experience a bluing of the skin at elevations above 2,500 meters. This bluing of the skin is known as __________.
cyanosis
stratum basale
deepest cell layer of the epidermis. lies closest to the dermis and is connected to it along a wavy borderline that resembles corrugated cardboard. this basal layer contains the most adequately nourished of the epidermal cells because nutrients diffusing from the dermis reach them first. These cells are constantly dividing, and millions of new cells are produces daily.
Which glands play a role in thermoregulation?
eccrine glands
subcutaneous tissue (hypodermis)
essentially adipose tissue. not considered part of the skin, but it does anchor the skin to underlying organs and provides a site for nutrient (fat) storage. serves as a shock absorber and unsulates the deeper tissues from extreme temp changes outside the body.
Which type of skin cancer the least common but is the cause of most skin-cancer-related deaths?
melanoma
Which structures are located in the epidermis?
merkel
keratinocytes
most cells in epidermis produce keratin the fibrous protein that makes the epidermis a tough protective layer.
Which cavity would be lined with a mucous membrane?
oral
melanin
pigment that ranges in color from yellow to brown to black and is produced by spider shaped cells called melanocytes, found chiefly in the stratum basale.
What is the function of the keratin found within skin cells?
prevents water loss
Under which of the following conditions would a decubitus ulcer form?
prolonged bed rest after a severe back injury
Keratin
protein in the uppermost layers of the skin that results in a cornified or hardened exterior to help prevent water loss from the body surface
epidermal dendritic cells
scattered in epidermis important in alerting and activating immune syster cells to a threat as bacterial or viral invasion.
What prevents skin from becoming brittle?
sebum
What type of burn does a patient have if blisters are present and the affected area is painful?
second degree
What type of membrane lines the compartments of the ventral body cavity and produces a lubricant that allows organs to move against neighboring organs without friction?
serous membrane
What type of tissue makes up the epidermis of the skin?
stratified squamous epithelium
Which layer of the epidermis contains the greatest concentration of keratin?
stratum corneum
What epidermal layer consists of multiple layers of living keratinocytes and scattered dendritic cells?
stratum spinosum
stratum coneum
20 to 30 layers thick but accounts for about three quarters of the epidermal thickness. shingle like dead cell remnants, completely filled with keratin. referred to as cornified or horny cells
What is the function of epidermal dendritic cells?
Ingest foreign substances and activate the immune system
Functions of the Integumentary System
Protects deeper tissues from mechanical, chemical, thermal (hot or cold) and bacterial damage, ultraviolet radiation and dessication, it also aids in body heat loss or heat retention as controlled by the nervous sytem, aid in excretion of urea and uric acid, and synthesizes vitamin D
Which type of skin cancer is the least malignant but most common?
basal cell
What condition occurs when hemoglobin is deprived of oxygen?
cyanosis
Cutaneous Membrane
the skin, supercicial epidermis composed of keratinizing stratified squamous epithelium while the underlying dermis is mostly dense fibrous connective tissue, exposed to air as a dry membrane
Serous Fluid
thin, clear, fluid that secreted by both the visceral and parietal membranes and lies in small space between them, it allows the organs to slide easily along the cavity walls without friction for routine function (pumping heart, churning stomach)
What type of burn damages the skin so severely that regeneration of the damaged tissue is NOT possible?
third-degree burn
Dermis
underlying, mostly dense connective tissue. your "hide". strong stretchy material that helps to bind the body together.
Which organic compound is produced by skin cells?
vitamin D