Dermis Flashcards
Dermis
•Connective tissue
• Underlies the epidermis
2 layers of the dermis:
• papillary layer
• reticular layer
Upper dermal regions contain projections called dermal papillae
Papillary layer
Indent the epidermis above
Many projections contain. capillary loops, and other house pain and touch receptors.
On palm and sole surfaces, paillar increase friction and gripping ability.
Fingerprints are identifying films of sweat.
Papillae layer
Deepest skin layer
Reticular layer
• Blood vessels
• sweat and oil glands
• deep pressure receptors
Lamellar corpuscles
Other dermal features
• cutaneous sensory receptors
• phagocytes
• collagen and elastic fibers
• blood vessels
Yellow, reddish brown, or black pigments
Melanin
Orange-yelloe pigment from some vegetables
Carotene
• Red coloring from blood cells in dermal capillaries
• Oxygen content determines the extent of red coloring
Hemoglobin
Due to embarrassment inflammation, hypertension, fever, or allergy.
Redness (erythema)
Due to emotional stress (such as fear), anemia, low blood pressure, impaired blood flow to an area.
Pallor (blanching)
Indicates a liver disorder
Jaundice (yellow cast)
Hematomas
Bruises (black and blue marks)
Cutaneous glands are all exocrine glands
• sebaceous glands
•< sweat glands
•Located all over the skin except for palms and soles
• Produce sebum (oil)
• most have ducts that empty into hair follicles;, other open directly onto skin surface
• glands are actived at puberty
Sebaceous (oil) glands
• produce sweat
• widely distributed in skin
Sweat (sudoriferous) gland
2 types of sudoriferous glands
• eccrine glands
• Apocrine glands
Open via duct to sweat pores on the sklns surface
• produce acidic sweat
• function in body temperature regulation
Eccrine gland
•Ducts empty into hair follicles in the armpit and genitals
• Begin to function at puberty
• Release swear that also contains fatty acids and proteins
• Play a minimal role in the body temperature regulation
Apocrine glands
• consist of hart keratinized epithelial cells
• melanocytes provide pigment for hair color
• hair grows in the matrix of the hair bulb kn stratum basale
Hair
• Central medulla
• Cortex sorrounds medulla
• cuticle on outside of cortex
Hair anatomy
• Heavily keratinized, scale-like modifications of the epidermis
• Stratum basale extends beneath the nail bed, which is responsible for growth
• Lack of pigment makes nails colorless
Nails
• caused by fungal infection (Tinea pedis)
• Itchy, red peeling skin between the toes
• Athlete’s foot
• Caused by inflammation of hair follicles
• carbuncles are clusters of boils caused by bacteria
• Boils (furuncles) and carbuncles
• Caused by human herpesvirus 1
• Blisters itch and sting
Cold sores (fever blisters)
• Caused by exposure to chemicals that provoke allergic responses
• Itching, redness, and swelling of the skin
• Contact dermatitis
• caused by bacterial infection
• link, fluid raised lesions around mouth/nose
Impetigo
Triggered by trauma, infection, hormonal changes, or stress
• red, epiderma lesions covered with dry, silvery scales that itch, burn, crack, or sometimes bleed
Psoriasis
• Tusse damage and cell death caused by heart
•< Results in loss of body fluids and infection from the invasion of bacteria
Burns
Body is divided into _____ areas for quick estimation
11
• Body is divided into 11 areas for quick estimation
•< each area represent s about 8 percent of total body surface area
• The area sorrounding the genitals (the perineum represent 1 percent of body surface area
Homeostatic imbalance of skin
• only epidermis is damaged
• skin is red and swollen
First- degree burn +superficial burn)
• epidermis and the superficial part of dermis are damaged
• skin is red, painful, and blistered
• regrowth of the epithelium can pccur
Second- degree burn (partial-thickness burn)
• destroys epidermis and dermis; the burned area is painless
•requires skin grafts, as regeneration is possible
• burned area is blanched (gray-white) or black
Third-degree burn (full thickness burn
• extends int deeper tissues (bone, muscle, tendons)
• Appears dry and leathery
• requires surgery and grafting
•< may require amputation
Fourth- degree burn,(bone,muscle, tendons)
Over _____ percent of body has second-degree burns
30
Over _____ percent of the body has third or fourth-degree burns
10
Thirds pr fourth-degree burns of the:
Face, hands, or feet, genitals
• most common form of cancer in humans
• most important risk factor is overexposure to ultraviolet (UV) radiation in sunlight and tanning beds
Skin cancer
Cancer can be classified two ways:
Benign and malignant
Means the neoplasm (tumor) had not spread
Benign
Means the neoplasm has invaded other body areas
Malignant
Most common types of skin cancer:
• basal cell carcinoma
• squamous cell carcinoma
• malignant melanoma
•Least malignant and most common type of skin cancer
• Arises from cells in stratum basale that are altered so that they can no longer make keratin
• lesions appear as shiny, dome-shaped nodules that develop a central ulcer
Basal cell carcinoma
• Believed to be induced by UV.exposure
• Arises from cells of stratum spinosum
• Lesions appear as scaly, reddened papules that gradually dorm shallow ulcers
• early removal allows a good chance of cure
• mestasizes to limph nodes if not removed
Squamous cell carcinoma
• most deadly of skin cancers, but accounts for only 5 percent of skin cancers
• arises from melanocytes
• mestasizes rapidly to lymp and blood vessels
• detection uses ABCDE rule for recognizing melanoma
Malignant melanoma
Two sides of pigmented mole do not match
Assymetry
A downy hair, covers the boat by the fifth or sixth month of detail development but disappears by birth.
Lanugo
An oily covering, is apparent at birth
Vernix caseosa
Small white spots, ate common at birth and disappear by the third week
Milia
May appear during adolescence
Acne
