Transcript Appendages of the Skin

Appendages of the Skin
ANATOMY & PHYSIOLOGY
INTEGUMENTARY SYSTEM
PART 2
Skin Appendages
 Glands
 all
arise from stratum basale then extend into
dermis & subcutaneous layers
 all exocrine glands
Release
product thru a duct onto surface of skin
 Hair & Hair Follicles
 Nails
Cutaneous Glands
1. Sebaceous (Oil) Glands
2. Sweat Glands
Sebaceous Glands
 All over body except soles & palms
 most ducts empty onto hair follicle, rest empty
directly onto skin
Sebaceous Glands Secrete Sebum
 Sebum:
 Oily
substances + fragmented cells
 Become more active in puberty (androgen effect)
 Function:
keeps
skin soft & moist,
prevent hair from becoming brittle
kills
bacteria
Sebaceous Gland
 If duct becomes blocked  whitehead forms
 With time oxidizes  blackhead forms
 If becomes infected  pimple
Seborrhea (Cradle Cap)
 Seen in newborns & infants
 Due to overactivity of sebaceous glands
 Starts as pink, raised lesions  form yellow to
brown crust  sloughs off as oily dandruff
Sudoriferous Glands
 aka sweat glands
 1 body has > 2.5 million
 2 Types:
1. Eccrine glands
2. Apocrine glands
Eccrine Sweat Glands
 more of these than apocrine sweat glands
 Product: Sweat
 Sweat is made up of:
 Water
 NaCl
 Vitamin
C
 Urea & uric acid
 Lactic acid
Eccrine Glands
 Important part of thermoregulation function of skin
 Nerve endings send action potential when body
temperature or external temperrature > normal
 When water in sweat evaporates body cools due to high
heat of vaporization of water
Apocrine Sweat Glands
 In axilla and genital areas
 Usually larger than eccrine glands
 Ducts empty into hair follicles
 Begin to function during puberty
 If infectedwith bacteria  odor
 Product:
 Fatty acids
 Proteins
 + what is in eccrine sweat
Hair Follicles
 Scattered all over body except palms & soles
 Functions:
 Protection
 Insulation
Hair Follicles
Nails
Homeostatic Imbalances
 Skin is largest organ so see many skin conditions
 Most common ailments fall into categories
1.
2.
3.
4.
Infections
Allergies
Skin cancer
Burns
Homeostatic Imbalances of the
Skin
INTEGUMENTARY SYSTEM
PART 3
Bacterial Infections
 Boils & Carbuncles
 Infected
sebaceous glands (especially neck)
 Staphylococcus
areus
Impetigo
 See blister-like pink lesions around nose, mouth 
yellow crusty
 Elementary school age
 Extremely contagious staph
Athlete’s Foot
 Itchy, red, peeling
 Usually starts between toes
 Tinea pedis
Cold Sores(Fever Blisters)
 Herpes simplex
 Red, blisters, sore
 Virus remains dormant in cutaneous nerve
 Herpes is Forever
Contact Dermatitis
 Itching, redness, swelling
 Skin reacting to metal, chemical (in food, poison ivy)
Psoriasis
 Chronic condition
 Scaly, red to silvery scales
 Frequently starts on elbow, knee , scalp: can spread
 Treatment: cortisone cream
Burns
 Tissue damage & cell death caused by intense heat, cold,
electricity, UV radiation, acids
 Rule of Nines:
1st Degree Burns
 Only epidermis is damaged
 Heals after 2-3days discomfort
 Example: sunburn
2nd Degree Burn
 Epidermis & upper dermis damaged
 Red, blisters, painful
 Regeneration possible
 With 1st degree burns :
 Partial
thickness burns
3rd degree burns
 Full thickness burn: damage to all layers of skin
 Not painful (nerve endings destroyed)
 Regeneration not possible
 Skin grafting
Skin Cancer
 Fastest rising cancer in young adults
 3 kinds:
Basal Cell Carcinoma
2. Squamous Cell Carcinoma
3. Malignant Melanoma
1.
4. Metastasis to Skin
Basal Cell
 Starts in stratum basale
 Slow, rare to metastasize
 Very common in sun-exposed areas
 #1 cause:sun exposure
Squamous Cell Carcinoma
 Stratum spinosum
 Less common, more likely to metastasize
 Sun exposed areas
Malignant Melanoma
 5 % of skin cancer but the deadliest
 Risks
 Family
history
 Changing mole
 History of severe sunburns, tanning bed use
 Treatment: surgery, chemotherapy
Malignant Melanoma
ABCD Rule
 A: asymmetry, pigmentation not uniform
 B: border irregularity
 C: colors vary in same spot
 D: diameter > end of pencil eraser
Tattoos
 Needle injects ink into derrmis
 Pigment can migrate, safety not well established
 Needle infections not uncommon
C  liver cancer
 LASER to remove
 Hepatitis
Development of the Skin

Lanuga: soft , fine hairs that develop in 5th -6th month
of pregnancy

Vernix caseosa: creamy, thick, white substance produced
by sebaceous glands in 2nd half pregnancy
 Keeps skin soft, moist
Development of the Skin

Milia:small white spots frequently seen on newborn –
3rd week after birth
 Accumulations in sebaceous glands
Skin Changes with Aging
 Subcutaneous tissues decrease leading to:
1.
2.
3.
4.
Intolerance to cold
Skin drier due to decreased oil production & less
collagen fibers
More likely to bruise
Decreased elasticity (baggy skin)