Physiology Of The Integumentary System Flashcards
Physiology of the Integumentary System
Protection
Sensation
Vitamin D Production
Temperature Regulation
Immunity
Excretion
Plays an important role in reducing water loss because its lipids act as the barrier to the diffusion of water
Intact Skin
Prevents microorganism and other foreign substances from entering the body.
Skin
Protects underlying structures against abrasion
Stratified Squamos Epithelium
Absorbs ultraviolet light and protects underlying structures from its damaging effects
Melanin
acts as heat insulator
Hair on the head
keep sweat out of the eye
eyebrows
Protects the eyes from foreign objects
Eyelashes
Prevents the entry of dust and other material in ears or nose
Hair on the nose and ears
Protects the end of the fingers and toes from damage and can be use in defense
Nails
Receptors in the epidermis and dermis can detect:
Pain
Heat
Cold
Pressure
Although hair does not
have a nerve supply,
sensory receptors
around the hair follicle
can detect the
movement of hair
It is formed when the skin is exposed to ultraviolet light
Precursor Molecule of Vitamin D
The precursor is carried by the
____ to the ____, where it is
modified, and then to the
____, where the precursor
is modified further to form
____.
Blood to the Liver
Kidneys
Active Vitamin D
stimulates the small
intestine to absorb calcium and
Vitamin D
important because the rate of chemical
reactions within the body can be increased or decreased by changes in body temperate
Regulation of Body Temperature
Factors that tend to Raise Body Temperature
Exercise
Fever
Increase in Environmental Temperature
Dilate and
enable more blood to flow within the skin, thus transferring heat from deeper tissues to the skin
Blood vessel in dermis
Acts as a
barrier that prevents direct
entry of pathogen
Immunity
defensins
Antimicrobial peptides (AMPs)
Sphingomyelin
Cathelicidins and lipids
acts as a biomolecular barrier that disrupts bacterial
Glucosylceramides
plays a minor role
in excretion, the removal
of waste products from the
body
Integumentary System
Sweat contains small
amounts of waste products,
such as:
Urea
Uric Acid
Ammonia
2 Ways of Tissue Repair (Wound Healing)
Regeneration
Fibrosis
Replacement of destroyed tissue by the same kind of cell
Regeneration
Repair by dense (fibrous) connective tissue (scar tissue)
Fibrosis
Complete restoration of organ structure and function after an injury
Regeneration
Phase of tissue repair in which connective tissues replaces parenchymal tissues
Fibrosis
Complete restoration of of the structure of the damaged is possible
Restoration
Restores some original structure but can cause structural derangements
Fibrosis
Restores the function of the tissue
Regeneration
Leads to loss of function in the tissue
Fibrosis
Without Scar Formation
Regeneration
With Scar Formation
Fibrosis
Events of Tissue Repair
Hemostasis
Inflammation Sets the Stage
Granulation Tissue Forms
Regeneration and Fibrosis Affect Permanent Repair
body’s natural reaction to an injury that stops bleeding and repairs the damage. This capability is usually for your benefit, conserving blood and preventing infections
Hemostasis
body’s natural reaction to an injury that stops bleeding and repairs the damage. This capability is usually for your benefit, conserving blood and preventing infections
Hemostasis
Capillaries become very permeable
Clotting proteins migrate into the area from the bloodstream
A clot walls off the injured area
Inflammation Sets the Stage
Physical Effects of Inflammation
Swelling
Pain
Heat
Growth of new capillaries
Angiogenesis
•Growth of new capillaries (angiogenesis)
•Phagocytes dispose of blood clot
•Mesenchymal cells replaced by fibroblasts
•Rebuild collagen fibers
Granulation Tissue Forms
Scab Detaches
Whether the scar is visible or invisible depends on the severity of the wound
Regeneration and Fibrosis Affect Permanent Repair
Tissue that regenerate easily
Epithelial tissue (skin and mucous membranes)
Fibrous connective tissues and bone
Tissue that regenerate poorly
Skeletal muscle
Tissue that are replaced largely w/ scar tissue
Cardiac Muscle
Nervous Tissue within the Brain and Spinal Cord
Injury to a tissue caused by heat, cold, friction, chemicals, electricity and radiation
Classified according to its depth
Burn
Part of stratum basale remains viable, and regeneration of the epidermis occurs from within the burn area, as well as from the edges of the burn
Partial thickness burns
Types of Partial Thickness Burns
First-degree burns
Second-degree burns
Third-degree burns
Involved only the epidermis
Red and painful
Slight edema or swelling
First-degree burn
Damage both Epidermis and Dermis
Dermal Damage is minimal - redness, pain, edema blister
When burn goes deep into the dermis - wound appear ref, tan, /white, several months to heal and forms scar
Second-degree burn
Epidermis and Dermis is completely destroyed
Recovery occurs from the edges of the burn wound
Surrounded by areas of first and second degree burns
Usually painless as sensory receptor in epidermis and dermis is destroyed
White, tan, brown, black or deep cherry red
Third-degree burn
General terms for different integumentary carcinomas
Skin cancer
Abnormal growth of skin cells
Skin Cancer
Types of Skin Cancer
- Basal Cell Carcinoma
- Squamos cell carcinoma
- Malignant Melanoma
Most frequent type, begins with cells in the stratum basale and extends into the dermis to produce ___
Basal Cell carcinoma
Open ulcer
surgical removal and rafiation therapy cures this type of cancer
Basal Cell Carcinoma
develops from cells immediately superficial to the stratum basale
Undergo little no cell division, the cell continue to divide as they produce ____
Nodular, keratinized tumor confined to the epidermis
Squamos Cell Carcinoma
Keratin
Rare form of skin cancer that arises from melanocytes, usually in preexisting mole
Metastasis is common and unless diagnose and treated early in development this cancer
Malignant Melanoma
Aggregation or “nest” of melanocytes
Mole
appears as flat, large, spreading lesion or as deeply pigmented nodule
Melanoma
How to avoid any form of cancer?
Limiting exposure to sun
Use of sun protection to block UV light
Classified into two types based on their wavelength
Ultraviolet Light
Types of Ultraviolet Light
UVA
UVB
Longer wavelength
UVA
Shorted wavelength
UVB
Exposure to this causes more tanning of the skin but is associated with development of malignant melanoma
UVA
Exposure to this causes most burning of the skin and is associated with the development of sunburn, tanning, sun spot and blistering which also can lead to skin cancer
UVB
As the body ages the skin is?
more easily damaged
Aging affects
Skin Infection are more likely
Repair of skin occurs more slowly
Decrease in the activity of elastic fibers in the dermis and loss of adipose tissue from subcutaneous tissue cause skin to
Sag and Wrinkle
Decrease in the activity of sweat glands and in the blood supply to the dermis results in
Reduced Ability to Regulate Body Temperature
As sebaceous gland activity decreases.. The skin
Becomes drier
caused by increase melanin production
freckles
Generally, melanocytes decreases as age increases but no. of melanocytes increases in some area is possible to form or produce
Age Spot
gray and white hair is due to
Decrease in or Lack in Melanin Production
