Transcript College Anatomy Lecture 5 The Integumentary System

College Anatomy
Lecture 5
The Integumentary System
Southern Boone County High School
Bill Palmer
College Anatomy
Integument-Background
The skin that covers your body
Includes nails, hair, sweat glands, and
sebaceous (fat) glands
Dermatology is the study of the skin
Skin is reflective of overall health
Much social emphasis on skin
College Anatomy
Integument-Background
The skin is our largest organ
1.5-2 square meters of skin/person
7-8% of body weight
1.5-4mm thick
Two main layers
Epidermis
Dermis
College Anatomy
Integument-Functions
Protection
Protects body from trauma, scrapes
Protects body from chemicals, toxins,
microbes
BUT, can absorb certain chemicals and
drugs-nicotine patch
Replaces itself
Protects from UV rays
College Anatomy
Integument-Functions
Prevent water loss
Water resistant
Prevents
unnecessary water
loss
Not totally
waterproof-allows
some fluids to
escape
College Anatomy
Integument-Functions
Temperature
Regulation
Capillaries in skin
help regulate
temperature
Too Hot-blood goes
to surface to cool
Too Cold-blood
stays internal
College Anatomy
Integument-Functions
Metabolic Regulation
Epidermis makes Vitamin D3 when
exposed to UV radiation
15 min of UV provides all needed D
Vitamin D converted to hormone that
regulates calcium and phosphorus
absorption in intestine
College Anatomy
Integument-Functions
Immune Defense
Cells in epidermis
attack pathogens
and epidermal
cancer cells
College Anatomy
Integument-Functions
Sensory Reception
Large sense organ-detects
Heat
Cold
Touch
Pressure
Texture
Vibration
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Integument-Functions
Excretion (Sweating)
Sensible Perspiration-normal sweat
Cools body
Water
Salts
Urea (nitrogen waste)
Sebaceous Glands
Secrete sebum-oil that lubricates skin
and hair
College Anatomy
Integument-Epidermis
Five Layers
1. Stratum Basale (basal layer)
2. Stratum Spinosum (spiny layer)
3. Stratus Granulosum (granular layer)
4. Stratum Lucidum (clear layer)
5. Stratum Corneum (horny layer)
College Anatomy
Integument-Epidermis
Five Layers
1. Stratum Basale (basal layer)-3 cell
types
Keratinocytes-Make new cells
Melanocytes-Produce pigments (brown,
yellow, black) these shield cell DNA from UV
rays
Tactile cells-sense pressure and produce
chemicals
College Anatomy
Integument-Epidermal Layers
Five Layers
2. Stratum Spinosum (spiny layer)
Cells from basal layers continue to grow and
specialize
Connections from cell to cell provide a spiny
look to cells
Also has cells that fight infection
College Anatomy
Integument-Epidermal Layers
Five Layers
3. Stratus Granulosum (granular layer)
Cells mature
Cells become thinner
Have more keratin-a protein
Become less permeable
Cell begins to die
Keratin remains
College Anatomy
Integument-Epidermal Layers
Five Layers
4. Stratus Lucidum
Very thin (3-5 cells thick)
Found only in thick skin-palms soles
College Anatomy
Integument-Epidermal Layers
Five Layers
5. Stratum Corneum (horny layer)
Most superficial layer
What you see
20-30 layers of dead cells with keratin
interlocked to make tough outer layer
About 2 weeks fro cells to go from basal
layer to horny layer
Dead cells last about 2 weeks on skin before
they are shed or washed away
College Anatomy
Integument-Thickness
Skin thickness varies over body
Thick Epidermis-2 mm thick
All 5 layers
Palms, Soles
Sweat glands, no hair, or sebaceous
glands
Thin epidermis-1 mm thick
Only 4 layers
College Anatomy
Integument-Color
Three proteins determine color
Hemoglobin-pink, red
Melanin-Yellow, red, tan, brown, black
Carotene-yellow-orange pigment
College Anatomy
Integument-Color
Abnormal Skin Color/Conditions
Albinism-No pigments
Bronzing-Gold skin due to Addison
Disease (adrenal cortex of Kidney)
Cyanosis-Blue skin-no oxygen
Erythema-redness of skin
Hematoma-bruise
Jaundice-Yellow skin (liver problem)
Pallor-Pale color
College Anatomy
Integument-Color
ADDISON DISEASE
CYANOSIS
ERYTHEMA
ALBINISM
PALLOR
HEMATOMA
JAUNDICE
College Anatomy
Integument-Markings
Nevus-mole, harmless, overgrowth of
melanin forming cells-may become
malignant due to UVB radiation
Freckles-less melanin than a nevus
Hemangioma-abnormality due to
excess blood vessels in skin
Strawberry birthmarks-Two types-may
disappear in youth or persist through life
Friction Ridges (fingerprints) -allow us
to pick things up
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Integument-Markings
FRECKLES
NEVUS
HEMANGIOMA
FINGERPRINT
College Anatomy
Integument-Dermis
Deep to epidermis
.5 to 4 mm thick
Two layers (Papillary and Reticular)
Contains several parts
Fibers
Sweat glands
Hair follicles
Sebaceous glands
Nail roots
Nerve endings
Muscle tissue
College Anatomy
Integument-Dermis
Papillary Layer
Supplies nutrients to epidermal layer
Sensory receptors
College Anatomy
Integument-Dermis
Reticular Layer
Network of connective tissue
Accessory structures
College Anatomy
Integument-Stretch marks
Weight gain, pregnancy stretch and
tear the collagen in the dermis
College Anatomy
Integument-Tension Lines
Places in body where collagen is
organized in same direction
Can not cut across these in surgeryknee, elbow, groin
College Anatomy
Integument-Nails
Nails-scale like modifications of the
epidermis on fingers and toes
Made of keratin
Free-edge (whitish part)
Nail body (pinkish part)
Nail root (part in skin)
Nail bed (part skin under nail)
College Anatomy
Integument-Nails
Nail Matrix-growing part of nail
Lunula-white moon shaped part of
nail with thick basal layer
College Anatomy
Integument-Hair
Hair-everywhere on body excepts
palms and soles, lips, parts of genitals
One hair is a pilus
Lanugo-fine baby hair, last trimester
of pregnancy and sometimes on
babies
Vellus-hair at birth
Terminal hair-normal adult hair
College Anatomy
Integument-Hair
LANUGO HAIR
LANUGO HAIR
ADULT TERMINAL
HAIR LOCATIONS
VELLUS HAIR
TERMINAL HAIR
College Anatomy
Integument-Hair
Hair Structure
Hair Bulb-swelling at the base of the hair
Hair Papilla-blood vessels and nerves
Hair Root-hair in the follicle
Hair Shaft-extends beyond the skin
College Anatomy
Integument-Hair
College Anatomy
Integument-Hair Functions
Protection-protect from injury and sunburn
Heat Retention-Hair on head prevents loss
of heat through top of head
Facial Expressions-Eyebrows
Sensory Reception-Detect touch
Visual Identification-hair characteristics
help determine sex, age, identification
Chemical Dispersal-hair helps to disperse
pheromones-attract opposite sex
College Anatomy
Integument-Hair Functions
Color-based on melanin in medulla of
hair (CSI)
Growth-Hair grows at the rate of a .3
mm/day to 1 m
Lose 10-100 hairs/day
VERY LONG HAIR
4.2 M
Captain Piccard
College Anatomy
Integument-Hair Glands
Merocrine Sweat Glands
3-4 million, most in palms, soles,
forehead
99% water, electrolytes, wastes
Aprocrine Sweat Glands
Armpits, nipples, groin
Contains proteins, lipids that are acted
on by bacteria and produce odor
Controlled by hormones after puberty
College Anatomy
Integument-Hair Glands
Sebaceous Glands
Produces oil-sebum
Keeps hair moist and flexible
Become active during puberty
Kill bacteria
Boil is a blocked duct in sebaceous
gland-usually lanced
College Anatomy
Integument-Clinical View
ACNE
Plugged sebaceous ducts
Comedo-sebaceous gland plugged with
sebum
– Whitehead
– Blackhead
Papule-dome shaped lesion with white blood
cells
Nodule-similar to nodule but extends deeper,
possible scar
Cyst-fluid filled nodule, probable scar
College Anatomy
Integument-Clinical View
COMEDO
NODULE
PAPULE
CYST
College Anatomy
Integument-Clinical View
SEVERAL GOOD TREATMENTS
Benzoyl peroxide-antibacterial
Salicylic Acid-unclogs pores
Antibiotics-kill bacteria (Dioxycycline,
Tetracycline, Erythromycin
Topical Retinoids-similar to vitamin Acontrols production of oil
Oral Retinoids-very good but may cause
birth defects (Accutane)
College Anatomy
Integument-Clinical View
BURNS
First-Degree-Sunburn, treat with cool
water, 3-5 days to heal
Second-Degree-Scald producing
blisters-treat with cool water, elevate
limbs to reduce swelling, do not break
blisters or add ointments, 2-4 weeks to
heal
Third Degree-Very serious, patient may
dehydrate, requires skin graft. Cover
lightly, no ointment, elevate.longed
healing
College Anatomy
Integument-Clinical View-Burns
First degree
Second degree
Third degree
College Anatomy
Integument-Clinical View
Skin Graft
College Anatomy
Integument-Clinical View-Moles
Three types of skin cancer
Basal Cell Carcinoma-90%-light fair
skinned people-sun major cause
Squamous Cell Carcinoma-20%-light fair
skinned people, sun major cause
Melanoma-Less common but causes
most deaths-often begins as a Nevus
(mole) and then turns cancerous
Tanning Bed = Sun
College Anatomy
Integument-Clinical View-Moles
Melanoma is a type skin cancer
1,000,000 people/year are diagnosed
Look at moles for the following
characteristics
A
B
C
D
College Anatomy
Integument-Clinical View-Moles
A-Asymmetrical
B-Border
C-Color
D-Diameter
College Anatomy
Integument-Clinical View-Moles
MELANOMA
METASTISIZED
MELANOMA
SQUAMOUS
BASAL
CARCINOMA
CARCINOMA
College Anatomy
Integument-Wrap up Activities
1. Make a drawing of a section of skin. Use
page 116 in Takahashi as a guide. Label.
2. Complete lab 11 in lab book. Read Chap.
6. Do Review Exercises 1-27 page 191.
3. Make a set of index cards with all skin
terms and their definitions.
4. Make a chart showing acne, burns, and
skin cancers. Their names, causes,
symptoms, and treatments.