lecture test 2.txt

Cutaneous and Accessory

Barrier, thermoregulation, sensations, Waste removal, immune, blood reserve, vit D synthesis

• Epidermis - stratified squamous epithelium
• Dermis - areolar CT and dense CT
• Subcutaneous layer or hypodermis - adipose and areolar CT

Integumentary

Pain, pressure, temp and touch

Provides info to the central nervous system about the state of the body plus its other fxns the skin participates in homeostasis.

• Stratum Basal
• Stratum spinosum
• Stratum Granulosum
• Stratum Lucidum
• Stratum Corneum

• basal cells, merkel cells and melanocytes.
• fxn: Layer interlocks with dermis and new cell production

• 8-10 layers of keratinocytes that migrated from stratum basal as well as dendritic cells which stimulate immune response
• fxn: Immunity stimulation and cell division to increase thickness

• 3 - 5 layers of karatinocytes that migrated from stratum spinosum.
• fxn: produce keratin making cells thinner and flater and membranes to thicken and become less permeable.
• produce keratohyalin which causes cells to dehydrate, die and form tight layer with keratin fibers.

• Found only in thick skin areas like soles and palms. Extra layers of dead cells.
• fxn: increase thickness and protection against pressure and wear and tear.

• Outermost layer of skin. 15-20 layers of dead keratincytes - full of keratin
• fxn: barrier layer. waterproof due to keratin. protect from loss and microbe entry

The design of the stratum basal which has finger like extension down into the dermis. Provides more surface area to attach to the dermis.

cells that produce keratin

tough fibrous protein component of nails, hair and calluses as well as the general integumentary surface.

cells that produce melanin

yellow-brownish pigment that is transferred to neighboring keratinocytes. This pigment gives the skin its color. All people have the same number and distribution of malanocytes. It is the activity level of the cells that vary between individuals.

localization of overactivity of melanocytes

a condition where one's melanocytes have been destroyed resulting in patches of lighter skin. Patches will typically spread.

Carotene

in the dermis and it is made of areolar tissue.

capillaries, lymphatics and sensory neurons that supply the surface of the skin.

in the dermis deep to the papillary region and is made of dense irregular CT with collagen and elastic fibers and Adipose

hair follicles, sebaceous glands, nerves and sweat ducts.

Dermis

Because of elastin, elastic can be stretched and will recoil. Because of collagen, skin is extensible which means it can extend but doesnt mean it will recoil. Sometimes results in stretch marks

• Reticular layer of the dermis
• fxn: location/tube for hair growth

• portion of hair located in hair follicle that goes from bulb and goes 1/2 way to surface.
• fxn: It anchors hair into skin

• in the papillary layer of the dermis where it connects to the sheath surrounding the hair follicle.
• fxn: makes hair stand on end due to emotional or temperature stimuli. In animals it is a method to keep warm/insulated.

• Merocrin sweat glands and apocrine sweat glands are found in the Reticular layer of the dermis
• fxn: merocrin sweat glands help control body temp, flush toxins and provide traction.

• Reticular layer of the dermis wrapped around the base of each hair.
• fxn: sensory neuron that is sensitive to movement of the hair.

• layer deep to the dermis comprised of loose fibrouse CT and adipose tissue.
• fxn: stabilize the skin position or anchor it. it is thick, vascular and innervated. It also cushions large vessels, muscles and bones as well as insulate.

Sebaceous glands, merocrine and apocrine sweat glands and ceruminous glands.

• located in the epidermis
• fxn: sense fine touch and or pressure in very precise location

• in the dermal papillary layer
• fxn: sensitive to pressure, low frequency vibration and change in shape and touch.

• deep in the dermis
• fxn: sense deep pressure and vibration

• deep reticular layer
• fxn: sense changes in tension or shape of skin because changes tug on collagen fibers. Does not adapt meaning response will continue until you make change

• found in the epidermis
• fxn: sense temp and pain along with some light touch to avoid more serious tissue damage.

watery sweat

sticky, smelly, and thick sweat

sebum - mix of lipids, lysozyme (anit-microbe enzyme), and proteins

cerumen - earwax

directly on the skin

into the hair follicle

abrasion, incision, laceration, puncture, contusion

cut with jagged edges

bruise - bleeding but blood trapped in dermis.

• Inflammatory phase
• Migratory phase
• proliferative phase
• maturation phase

• increased blood flow, swelling, pain, redness, chem release attracts phagocytes
• blood fills wound and forms scab and fibroblasts appear at edges of injured area

phagocytes move in and continue to move in to remove debris and epithelial cells and fibroblasts migrate under scab to start forming new epidermis

• Rapid epidermal cell division and growth
• Collagen fibers from fibroblasts form scar tissue
• blood vessels are reestablished

• scab sloughs off
• Collagen is organized and fibroblasts decrease in numbers but as the dermis continues to heal, the tissue gets thicker - raising a scar.

Protect for UV rays, conserve heat, sensory input and protection of areas such as the eyes

nail bed, free edge, cuticle, nail root, nail body

decreased cell replacement, thinner skin, slower healing, less hair, less collagen (more delicate), less elastin (more wrinkles), less pigment (less UV protection) and less oil (dry skin)

4

• extent - amount of surface area covered
• depth - what layers are affected.

epidermis only - red, mild pain, low risk of scaring

mostly epidermis but may reach dermis in center of burn, red, pain, blisters, minimal scaring, increase risk of infection when blisters break open.

destroys epidermis, damage may reach the hypodermis, high risk for infection, may be no pain initially, dehydration, grafting may be necessary.

burn thru all skin and hypodermis! Damage to muscle, bone and deep fascia. Affects circulation. Great risk of death.

Age, amount of sun exposure over the years, genetics and pale skin

• Basal cell carcinoma
• Squamous cell carcinoma
• Malignant melanoma

• located in stratum basal
• most common form of skin cancer
• often caused by UV radiation and virtually never spreads

common, rarely spreads, restricted to sun exposed areas, rarely spreads.

cancerous melanocytes grow quickly and matastasize through the lymphoid system. outlook is grim.

scar that has spread past original injury. it is dark and shiny in appearance and people who burn earier are at greater risk

lacks pigmentation and typically along original lines/borders of injury . Lacks pigmentation.

• A - Asymmetry
• B - Border
• C - Color
• D - Diameter