Membranes and Skin

4.1.1_____ List the general functions of each membrane type-cutaneous, mucous, serous, and synovial-and 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)
  • ______stratified squamous epithelium
  • Dense fibrous connective tissue
  • Exposed to air so it is a ______membrane

Epithelial Membranes (Con’t)

  • ______Membranes – lines all body cavities that open to the ______
  • Epithelium (stratified squamous, simple columnar)
  • Loose connective tissue (lamina propria)
  • ______membranes – continuously bathed in secretions (usually mucus, but not always)

Epithelial Membranes (Con’t)

  • Serous Membranes – line body cavities that ______open to the exterior
  • Simple squamous epithelium
  • ______connective tissue (thin layer)
  • ______layer lines the wall of the ventral body cavity
  • Visceral layer lines the outside of the organs
  • Layers are separated by serous fluid (reduces friction)
  • 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
  • Soft areolar connective tissue (no epithelium)
  • Provide a ______surface
  • 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

  • Cells begin to ______as they are pushed upwards
  • Increasingly fills with ______(keratinized)
  • 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

  • Upper area that contains the dermal papillae (______)
  • contains ______, free nerve endings, Meissner’s corpuscles (touch)

–Reticular region

  • Lower area that contains ______, sweat and oil glands, and Pacinian corpuscles (pressure)
  • Overall dermis structure

–______and ______fibers located throughout the dermis

  • Collagen fibers give skin its toughness
  • Collagen fibers help keep skin hydrated
  • 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
  • ______(yellow, reddish brown, black) in the epidermis
  • ______deposited in the stratum corneum and subcutaneous tissue
  • 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

  • embarrassment, fever, hypertension, inflammation or allergy

–______- paleness or blanching

  • Fear, anger, anemia, hypotension

–Jaundice – yellowing

  • Signifies a ______disorder
  • Excess bile pigments are absorbed and deposited in body tissues

–______- hematomas

  • Sites where blood has escaped from the circulation and then clotted in the tissue space.
  • 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
  • Eccrine
  • 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 ______
  • Sebaceuos glands (oil)
  • Sweat glands

*exocrine glands release to a specific site.

–Sebaceous Glands

  • Produce______
  • Sebum – mix of oil and cell fragments
  • lubricates skin and hair
  • ______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

  • ______per person
  • Two types
  • ______(ek’rin) – more numerous – found all over the body.
  • Apocrine (ap’ o-krin) – found in the ______and______areas
  • Eccrine Sweat Glands
  • Found all over the body
  • Produce sweat – made of water, salts, ______, and traces of metabolic wastes like urea, and ammonia.
  • ______(inhibits bacterial growth)
  • Exits the skin at sweat pores
  • Helps regulate body ______
  • Apocrine Sweat Glands
  • Found in the axillary and genital areas
  • ______thaneccrine glands
  • Ducts empty into hair follicles
  • Made of same substances as eccrine sweat plus ______and ______
  • Bacteria live on these nutrients and cause the unpleasant BO
  • Function almost ______
  • Ceruminous Glands
  • modifiedeccrine sweat glands, found on the external ______.
  • ______(cerumen). Composed of a combination of sebum and secretion from ceruminous gland.
  • 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
  • Found almost everywhere on human body
  • ______protrudes above skin surface
  • ______located below surface; base of root is the hair bulb
  • 3 main regions

Actual hair shaft

Hair follicle

Hair bulb

  • Has 3 concentric layers

______: Central axis

______: Forms bulk of hair

______: Forms hair surface

  • Hair follicle
  • ______- Dermal sheath: part of dermis that surrounds the epithelial sheath

Dermal Connective tissue, supplies blood to matrix in hair bulb

  • ______- 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
  • Internal ______is source of hair

Formed by division of well-nourished stratum basale epithelial cells

Daughters cells are pushed away and keratinize and die.

  • Contains ______
  • Dermis projects into bulb and is
    blood supply
  • Hair Color
  • Caused by varying amounts and types of melanin. Melanin can be black-brown and red.
  • Muscles. - ______pili.
  • Type of smooth muscle.
  • Muscle contraction causes hair to “stand on end”
  • Skin pushed up by movement of hair follicle

______

  • Hair Growth
  • ______- 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.

  • Regular hair loss means hair is being ______
  • 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