Membranes and Skin
4.1.1_____ List the general functions of each membrane type-cutaneous, mucous, serous, and synovialand give its location in the body.
4.1.2_____ Compare the structure (tissue makeup) of the major membrane types.
Classification of Body Membranes
 Epithelial Membranes - covering and lining membranes
 ______________ membrane – Skin (Integument)
o ______________ stratified squamous epithelium
o Dense fibrous connective tissue
o Exposed to air so it is a _______ membrane
 Epithelial Membranes (Con’t)
 ______________ Membranes – lines all body cavities that open to the ______________
o Epithelium (stratified squamous, simple columnar)
o Loose connective tissue (lamina propria)
o ______ membranes – continuously bathed in secretions (usually mucus, but not always)
 Epithelial Membranes (Con’t)
 Serous Membranes – line body cavities that ______________ open to the exterior
o Simple squamous epithelium
o ____________ connective tissue (thin layer)
o ____________ layer lines the wall of the ventral body cavity
o Visceral layer lines the outside of the organs
o Layers are separated by serous fluid (reduces
friction)
o Names depend upon locations
– Peritoneum – lines the abdominal
cavity
– _________ – surrounds the lungs
– Pericardium – surrounds the heart
 Connective Tissue Membranes
 ______________ Membranes – line the fibrous capsule surrounding joints
o Soft areolar connective tissue (no epithelium)
o Provide a ______________ surface
o Secrete lubricating fluid
Integumentary System
4.3.1 List several important functions of the integumentary system and explain how these functions are
accomplished.
 Consist of
 Cutaneous membrane (skin)
 Derivatives
– ____________ and oil glands
– Hair
– Nails
 Funtions
 Protection from ____________ and chemical
damage, thermal damage, bacterial invasion, UV
radiation, dessication
 Aids in ______ ______ or retention
 Aids in excretion of urea
 Synthesizes Vitamin D
– *Please see the chart on pg 95 for details
4.2.1 When provided with a model or diagram of the skin, recognize and name the major and minor
parts.
4.2.2 Name the layers of the epidermis and describe the characteristics of each
 Structure of the skin
 Epidermis – the ____________ layer
– Stratified squamous epthelium
– Keratinized – gets hard and tough
 Dermis - ___________ to the epidermis
– Made of dense connective tissue
– Collagen and elastic fibers
 Subcutaneous tissue or ____________
– Deep to the dermis (not part of skin)
– Adipose tissue – ____________ skin to rest of body
– Shock absorber/insulator/curves
 Epidermis
 Composed of 5 layers called ____________
*from the inside going out*
1. Stratum basale
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum
5. Stratum ____________
– The epidermis is ___________ – has no blood supply
 Stratum Basale
– Lies ___________ to the dermis
– Cells receive _______________ via diffusion from the
dermis
– Keratinocytes are constantly dividing
– Also called stratum germinativum
– Daughter cells are pushed ____________ to become
part of the upper epidermal layers
– Contains the ____________
 Stratum Spinosum and Stratum Granulosum
– Stratum Spinosum – 8 to 10 cell layers thick
– Stratum Granulosum – 2 to 5 cell layers thick
o Cells begin to ____________ as they are
pushed upwards
o Increasingly fills with _________ (keratinized)
o As the cell continues to push upwards, the nucleus and organelles ____________
and the cell __________
 Stratum Lucidum
– Several layers of ____________ cells that look transparent – only occurs where skin is
hairless (hands and feet)
– Too much keratin
– not enough nutrition or oxygen/to far from ____________
 Stratum Corneum
– 25 or more cell layers thick, containing soft keratin.
– ____________ like layers filled with keratin – cornified or horney cells
– Cells are continually shed as clothes rub against your body or when you wash.
– Completely new epidermis every ____________
– ____________ – an exceptionally tough protein
 Dermis
 This is your ____________
 Leather = dermis
 Dense fibrous connective tissue
 Two major regions
– ____________ layer
– Reticular areas
 Varies in thickness
– Ex. Hands vs. eyelids
 Dense fibrous connective tissue
– Papillary region
o Upper area that contains the dermal
papillae (_____________)
o contains _____________ , free
nerve endings, Meissner’s
corpuscles (touch)
– Reticular region
o Lower area that contains
_____________ , sweat and oil
glands, and Pacinian corpuscles
(pressure)
 Overall dermis structure
– _____________ and _____________
fibers located throughout the dermis
o Collagen fibers give skin its toughness
o Collagen fibers help keep skin hydrated
o Elastic fibers give skin elasticity
– As we age we loose collagen/elastic fibers and subcutaneous tissue making us _________
– Blood vessels play a role in body _____________ regulation
4.3.3 Name the factors that determine skin color and describe the function of melanin.
 Skin Color
 Three pigments contribute to skin color
1. _____________ (yellow, reddish brown, black) in the
epidermis
2. _____________ deposited in the stratum corneum and
subcutaneous tissue
3. Hemoglobin in the dermal blood vessels
 Melanin – FYI(steps of tanning)
1. Produced by cells called melanocites located in the
stratum basale layer of the epidermis.
2. Sunlight stimulates the production of _____________.
3. Stratum basale cells _________________________ the
pigment
4. Melanin forms protective layer over the sunny side of
nuclei.
5. _____________ and _____________ are spots of
concentrated melanin.

Other Influences on Skin Color
– _____________ – redness
–
–
–
o embarrassment, fever, hypertension, inflammation or allergy
______________ - paleness or blanching
o Fear, anger, anemia, hypotension
Jaundice – yellowing
o Signifies a _________ disorder
o Excess bile pigments are absorbed and deposited in body tissues
____________ - hematomas
o Sites where blood has escaped from the circulation and then clotted in the tissue
space.
o Possibly signifies a Vitamin C deficiency or hemophilia
Appendages of the Skin
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat
glands, and hair.
 Appendages of the skin
– ____________ glands
 Oil glands
 Sweat glands
o Eccrine
o Apocrine
– Hair and hair follicles
– ____________
 Cutaneous glands
– ____________ glands that release their secretions to the outside of the body
 Formed by the cells of the stratum basale but reside almost entirely in the ____________
o Sebaceuos glands (oil)
o Sweat glands
*exocrine glands release to a specific site.
– Sebaceous Glands
 Produce____________
o Sebum – mix of oil and cell fragments
o lubricates skin and hair
o ____________ bacteria
 Found all over the body except on palms of
hands and soles of feet
 Ducts usually empty into a
________________________
 If blocked by sebum, whitehead forms
 If material oxidizes and dries, ____________
is formed
 Acne is an active ____________ of the
sebaceous glands
– Sweat Glands - Sudoriferous glands
o ____________ per person
 Two types
o ____________ (ek’ rin) – more
numerous – found all over the body.



o Apocrine (ap’ o-krin) – found in the ____________ and ____________ areas
Eccrine Sweat Glands
o Found all over the body
o Produce sweat – made of water, salts, ____________, and traces of metabolic wastes
like urea, and ammonia.
o ____________ (inhibits bacterial growth)
o Exits the skin at sweat pores
o Helps regulate body ____________
Apocrine Sweat Glands
o Found in the axillary and genital areas
o ____________ than eccrine glands
o Ducts empty into hair follicles
o Made of same substances as eccrine sweat plus ____________ and ____________
o Bacteria live on these nutrients and cause the unpleasant BO
o Function almost ____________
Ceruminous Glands
o modified eccrine sweat glands, found on the external ____________ ____________.
o ____________ (cerumen). Composed of a combination of sebum and secretion from
ceruminous gland.
o Function- In combination with hairs, prevent dirt and insects from entry. Also keeps
eardrum ____________.
4.3.2 Describe the distribution and function of the epidermal derivatives – sebaceous glands, sweat
glands, and hair.
 Hair and Hair Follicles
– Protects head from bumps
– Shields the eyes ____________
– Keeps foreign particles out of ____________
– Used to provide ____________ – we wear
clothes now
 Hair
o Found almost everywhere on
human body
o ____________ protrudes above
skin surface
o ____________ located below
surface; base of root is the hair bulb
o 3 main regions
 Actual hair shaft
 Hair follicle
 Hair bulb
o Has 3 concentric layers
 ____________: Central axis
 ____________: Forms bulk of hair
 ____________: Forms hair surface
 Hair follicle
o ____________ - Dermal sheath: part of dermis that surrounds the epithelial sheath
 Dermal Connective tissue, supplies blood to matrix in hair bulb
o ____________ - Epithelial sheath with internal and external parts.
 Forms the hair
 Internal part contains stratum basale that may remain after injury and supply a
source of new epidermis
 When hairs are pulled out, internal part comes out and is visible as white bulb




Hair bulb
o Internal ____________ is source of hair
 Formed by division of well-nourished stratum basale epithelial cells
 Daughters cells are
pushed away and
keratinize and die.
o Contains ____________
o Dermis projects into bulb and
is
blood supply
Hair Color
o Caused by varying amounts
and types of melanin. Melanin
can be black-brown and red.
Muscles. - ____________ pili.
o Type of smooth muscle.
o Muscle contraction causes hair
to “stand on end”
o Skin pushed up by movement
of hair follicle
 ____________
Hair Growth
o ____________ - Growth and resting stages
 Growth: cells added at base and hair elongates. Average rate is ___________
 Rest: follicle shortens and holds hair in place. Then hair falls out of follicle.
New hair begins.
o Regular hair loss means hair is being ____________
o Permanent hair loss: pattern baldness most common cause
Homoeostasis of the Skin
4.4.1 Differentiate between first, second, and third degree burns.
4.4.2 Explain the importance of the “rule of nines.”
Burns
 Tissue damage and cell death caused by intense heat, _____________ , UV radiation or chemicals
 Leads to dehydration and electrolyte imbalance
 Can lead to _____________ – low blood volume
Rule of Nines
 Estimate of the amount of _____________ lost based on the total body surface burned.
 Body is divided into 11 areas each representing 9% of the total body surface area (11 x 9 = 99) and one area the
perineum makes up the remaining 1%
Burn Victims
 _____________ is the leading cause of death in burn victims
 Pathogens easily invade the burned areas and multiply rapidly (lots of food)
 I_____________ system becomes depressed
First-Degree
 Damage only the _____________
 Area becomes red and swollen
 Heals in _____________ days
 Sunburn
Second-Degree
 Involves injury to the epidermis and the upper region of the _____________
 Area becomes red and painful and blisters appear.
 Sufficient epithelial cells are still present so _____________ will occur
 Usually no scarring
Third-Degree




_____________ the entire thickness of the skin (epidermis and all of the dermis)
Appears gray-white or blackened
Burned area is _________ painful because the nerve endings are destroyed
Regeneration is NOT possible – skin grafting is done
Burns are Critical when:
 Over ________ of the body has second-degree burns
 Over _________ of the body has third-degree burns
 Third-degree burns on the face, hands or feet
4.4.3 Summarize the characteristics of basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.
 Skin Cancer
 Basal Cell Carcinoma
 Squamous Cell Carcinoma
 Malignant Melanoma
Basal Cell Carcinoma






Most _____________ and least malignant
Starts in stratum basale – cells can no longer form keratin and invade the dermis and hypodermis
Shiny, dome-shaped
Slow-growing
________ curable
Surgical removal
Squamous Cell Carcinoma
 Starts in the stratum spinosum
 _____________ rapidly and can metastasize to the lymph nodes
 Treated with surgical removal and radiation
 Scaly and red
Malignant Melanoma





Cancer of the _____________
Metastasizes quickly to lymph and blood vessels
____________ survival rate
Spreading black to brown patch
Stages of Melanoma
American Cancer Society






ABCDE Rule
A – Asymmetry – sides don’t match
B – Border irregular – not smooth
C – Color – different colors (black, brown, tan, blue, red)
D – Diameter – larger than 6 mm
E – Evolution – changes with time