Module 03: Integumentary System Flashcards
This system is composed of the skin and accessory structures, such as the hair, glands, and nails.
Integumentary System
What does the word integument mean?
Covering
What does the integumentary system signify?
The appearance of the integumentary system is an indicator of physiologic imbalances within the body.
This is the most vulnerable organ since it is exposed to microorganisms, lacerations, temperature extremes, harmful chemicals, and uv radiation.
Skin
What are the three (3) barriers of the skin?
(1) Chemical
(2) Physical
(3) Biological
What is the importance of the skin’s chemical barrier?
(1) Secretions and melanin
(2) Low pH of skin secretions which creates an acid bundle which actually retards to the multiplication bacteria and foreign substances
(3) Dermcidin in sweat and bactericidal substances in sebum
(4) Defensins - natural antibiotics
(5) Cathelicidins - protective peptides from wounded skin that prevents group A streptococcus bacteria
What is the importance of the skin’s physical barrier?
(1) Continuity of skin and harness of keratinized cells
(2) The thicker the epidermis - the more impenetrable
(3) Stratum corneum - outermost layer of the skin
This is the outermost layer of the cell and even if there are dead flat cells biding in it, it still serves it purpose in protecting the body from foreign substances.
Stratum Corneum
What are the substances that penetrate the skin?
(1) Lipid-soluble substances (Oxygen, Carbon Dioxide, and fat soluble vitamins A, B, E, K and steroids)
(2) Oleoresins of certain plants (Poison Ivy and Oak)
(3) Organic Solvents (Acetone, Dry Cleaning fluids, Paint Thinners)
(4) Salts of Heavy Metals (Lead and Mercury)
(5) Selected Drugs
What is the importance of the skin’s biological barrier?
(1) Dendritic cells
(2) Dermal macrophage
- part of the immune system and can engender an immune response by transferring the foreign substances to the lymph nodes
Functions of the Protection
(1) Reduction in body water loss
(2) Protects underlying structures against abrasion
(3) Protects underlying structures UV lights (melanin)
(4) Hair and Nail protection
What is the use of the hair protection?
Heat Insulator and protects from foreign materials
Which functions of the integumentary system affects the rate of chemical reactions?
Body Temperature Regulation
The Body Temperature Regulation is dependent on what?
The amount of blood flow beneath the skin’s surface and the activity of sweat in the skin
How does body temperature regulation happen?
Blood vessel dilates, which increases blood flow; thus increasing thermal (heart) loss within the epidermis
This pertains to sweating under normal conditions with an environmental temperature below 31-32 degrees Celsius. In this type of sweating, 0.5 liter of sweat is secreted per day. This is known as routine unknown and unperceivable sweating.
Insensible Perspiration
This pertains to sweating that occurs when there is a rise in body temperature, where the nervous system stimulates the dermal blood vessels to dilate to prompt the sweat glands into invigorous secretory activity. It can account to about 12 liters a day.
Sensible Perspiration
This assists in the loss of heat through evaporative cooling.
Sweat (fever)
These have the capacity to respond to stimuli arising outside of the body.
Exteroceptors
These receptors are part of the central nervous system made to detect pain, heat, cold and pressure.
Cutaneous Sensory Receptors
This is a vascularized layer of dense connective tissue which rests on the subcutaneous tissue.
Dermis
This is usually found in the deeper dermis or near the sub cutaneous tissue that alerts us to any bumps concerning deep pressure.
Lamellar or Pacinian Corpuscles
The exteroceptors are found in the hair that reports us any pressure with regards to the hair or where the direction of the wind is going.
Hair follicle receptors report
These exteroceptors scattered throughout the body which senses painful stimuli, like chemicals, extreme heat or cold, etc.
Free Nerve Endings
What does UV Light generate in metabolic functions?
UV Light causes the skin to produce a precursor molecule of vitamin D which is then carried by the blood to the liver (converts) and kidneys to forms an active form of vitamin D
This stimulates the small intestine to absorb calcium and phosphate for many body functions.
Vitamin D
How does the body help in excretion?
It also eliminates nitrogen containing wastes through the sweat such as ammonia and uric acid.
This is an important avenue for water and salt loss.
Profuse Sweating
How many surface area does the skin encompasses?
1.2 to 2.2 to square meters which is about 70% of the total body weight
This is the most superficial layer and the outermost protective shield of the body. It is a layer of epithelial tissue that rests on the dermis.
Epidermis
This is a layer of connective tissue in the skin.
subcutaneous tissue
How does the nutrients reach the epidermis?
The nutrients reach the epidermis by diffusing through the tissue fluid from blood vessels in the dermis.
What kind of membrane is the epidermis?
Cutaneous
What composes the epidermis?
(1) Keratinized stratified squamous epithelium
(2) Distinct layers called the strata
What is the main function of the epidermis?
prevent water loss and resist abrasion
What are the cells found in the epidermis?
(1) Keratinocytes
(2) Melanocytes
(3) Dendritic Cells
(4) Tactile Epithelial Cells
These cells produces keratin (fibrous protein protective properties) and are tied together by desmosomes for strength and water movement prevention.
Keratinocytes
This is a fibrous protein with protective properties.
Keratin
This cells synthesizes melanin that look like spider legs.
Melanocytes
These are membrane bound granules that form melanin.
Melanosomes
These cells are star shaped cells that are key activators in the immune system.
Dendritic Cells
Dendritic Cells are also known as
Langerhans Cells
These cells are found in the epidermal-dermal junction.
Tactile Epithelial Cells
The Tactic Epithelial Cells are also known as ________________.
Merkel cells
This is the basal layer or the deepest layer which consists of a row of stem cells that are continuously renewing signifying the youngest keratinocytes.
Stratum Basale or Stratum Germinativum
These reflect the rapid division of the stem cells.
Mitotic Nucleicin
How many percentage of melanocytes are in the stratum Basale?
10 to 20% (where they branch out intro a superficial layer known as the stratum spinosum layer)
These contain thick bundles of intermediate filaments, which consist of tension-resisting protein called the pre-keratin. This is the most abundant in the epidermal layer.
Stratum Spinosum
These are tension-resisting proteins that help the stratum spinosum scatter within keratinocytes with dendritic cells.
Pre-keratin
This is the thin stratum granulosum that consists of one to five cell layers, This is where the process of keratinization begins.
Stratum Granulosum
This is the process wherein the cell starts being filled with keratin which compels the cells to flatten and their nucleic organs begin to disintegrate and start accumulate two types of granules.
Keratinization
What are the two types of granules accumulated in keratinization?
(1) Keratohyalin Granules - helps to form keratin in the epidermal layer
(2) Lemerand Granules - contains water resistant glycolipids which are secreted in the extracellular space
These exteroceptors are associated with their sensory nerve endings and allows us to sense the feeling of clothes.
Tactile (Meissner’s) corpuscles in the dermal papillae and tactile epithelial cells
This is known as the clear layer and is found only in thick skin. And is composed of thin translucent bands and consists of few rows of flat, dead keratinocytes.
Stratum Lucidum
This is known as the horny layer and is the outermost layer of the skin and it sheds regularly. Moreover it is composed of glycolipids.
Stratum Corneum
This is composed of dense collagenous connective tissue containing fibroblasts, adipocytes, and macrophages. This is also where nerves, hair follicles, smooth muscles, glands, and lymphatic vessels extend to the dermis.
Dermis
These fibers are responsible for the structural strength and resistance to stretch.
collagen and elastic fibers
This layer of the dermis is a thin superficial layer composed of areolar connective tissue in which fine interlacing collagen and elastic fibers form a loosely woven mat.
Papillary Dermis
What does the loosely woven mat in the papillary dermis do?
It allows phagocytes or antigen to wander and patrol around the skin and impede foreign substances from further permeating.
These are projections towards the epidermis found in the upper part of the dermis, they also contain many blood vessels.
Dermal papillae
What composes a Dermal papillae?
(1) Capillary loops
(2) Free nerve endings for pain
(3) Touch receptors or tactile corpuscles (Meissner’s)
In thick epidermises, the dermal papillae lie on this, which in turn causes the overlying epidermis to form it
Dermal Ridges
These enhances to grip certain surfaces and can contribute to sense of touch by enhancing vibrations.
Friction Ridges
These friction ridges are actually genetically determined due to sweat pores along the crests, which leaves identifying films of sweat called _______________
Fingerprints
This composes 80% of the dermal layer which is made from a coarse, dense, regular connective tissue and this is where the network of blood vessels is found.
Reticular Dermis
This is known as the network of blood vessels is found and is named after the network of collagen fibers.
Dermal Vascular Plexus
These are separations between bundle forms and it is important to surgeons because when an incision is made parallel to these lines, the skin gapes less and heals more readily. This is more resistant to stretch.
Cleavage Texture lines
What are the factors that determine skin color?
(1) Pigments in the skin
(2) Blood Circulating
(3) Thickness of the Stratum Corneum
What are the two primary pigments in the skin?
(1) Melanin
(2) carotene
This is the group of pigments primarily responsible for the skin, hair, and eye color. This provides protection against ultraviolet light from the sun.
Melanin
Most melanin are what pigments?
Brown and black, yellowish or reddish
Melanin is produced by what?
Melanocytes
The melanin is packaged into vesicles called _____________.
Melanosomes
This is the yellow pigment found in plants such as squash and carrots
Carotene
These phagocytize the tips of the melanocyte cell processes therefore generating more melanosomes.
Epithelial Cells
These are generated when large amount of melanin form in some regions of the skin.
Freckles or Mole
Melanin production is determined by what factors?
(1) genetic factors
(2) exposure to light
(3) hormones
This is lipid soluble when consumed. It accumulates in the lipids of the stratum corneum and in the adipocytes of the dermis and subcutaneous tissue. If a lot of this is consumed, the skin can be yellowish.
Carotene
What is the other term for the skin?
Cutaneous membrane
This is where the cutaneous membrane rests. This attaches the skin to underlying bone and muscle and supplies it with blood vessels and nerves.
Subcutaneous Tissue (hypodermis)
What is the subcutaneous tissue?
It is loose connective tissue, including adipose tissue that contains half of the body’s stored lipids.
What is the function of the subcutaneous tissue?
(1) Insulation
(2) Padding
(3) can be used to estimate body fat
What is the acceptable fat body percentage in males?
13% to 25%
What is the acceptable fat body percentage in females?
21% to 30% because females have estrogen
Each hair arises from it. This is an invagination of the epidermis that extends deep into the dermis.
Hair follicle
This protrudes above the surface of the skin, and it is the root below the surface.
Hair shaft
This is the expanded base of the root (hair shaft), where the hair is produced
Hair bulb
This is the hard cortex that surrounds the softer center known as the _________________.
Medulla
The cortex is covered by this single layer of overlapping cells that holds the hair in the hair follicle.
cuticle
This is an extension of the dermis that protrude into the hair bulb and contains blood vessels.
Hair papilla
What are the two cycles of hair production?
Growth and resting stage
What happens during the growth stage?
Hair is formed by mitosis of epithelial cells within the hair bulb and these cells divide and undergo keratinization.
What happens during the resting stage?
The growth stops and the hair is held in the hair follicle.
Eyelashes grow for about ______________ days and rest for ___________ days
30 days and 105 days
The scalp hair grows for _________ years and rests for _____________ years.
3 years and 1 to 2 years
Each hair follicle is attached to smooth muscle cells called the _________________, which can contract and cause the hair to become perpendicular to the skin’s surface.
arrector pili muscle
What are the major glands in the body?
(1) Sebaceous glands
(2) Sweat Glands
These are simple, branched acinar glands, with most being connected by a duct to the superficial part of a hair follicle
Sebaceous glands
This is an oily, white substance rich in lipids and are released by holocrine secretion and lubricates the hair and the surface of the skin, which prevents drying and protects against some bacteria.
Sebum
What are the two kinds of sweat glands?
(1) Eccrine
(2) Apocrine
These sweat glands are simple, coiled, tubular glands and they produce a secretion that is mostly water with a few salt
Eccrine sweat glands
How do eccrine sweat glands secrete sweat?
merocrine secretion
What comprises eccrine sweat glands?
Eccrine sweat glands have ducts that open onto the surface of the skin through sweat pores and are for thermal regulation.
These are simple, coiled, tubular glands that produce a
thick secretion rich in organic substances.
Apocrine
Apocrine sweat glands become active at puberty because of the influence of _______________.
Sex hormones
where is the apocrine sweat glands usually found?
Axillary and anogenital regions (Slide 71)
This is a thin plate, consisting of layers of dead stratum corneum cells that contain a very hard type of keratin.
Nails
This is the visible part of the nail
Nail Body
This is the part of the nail covered by skin
Nail Root
This is a stratum corneum that extends onto the nail body and the nail root extends distally from the nail matrix
cuticle, or eponychium
These are epithelial tissue with a stratum Basale that
gives rise to the cells that form the nail.
nail matrix and bed
This is a small part of the nail matrix, can be seen through the nail body as a whitish, crescent-shaped area at the base of the nail.
Lunula
This is the excessive sloughing of stratum corneum cells from the surface of the scalp
dandruff.
In skin subjected to friction, the number of layers in the
stratum corneum greatly increases, producing a thickened
area called a ______________.
Callus
Over a bony prominence, the stratum corneum can thicken to
form a cone-shaped structure called the _________________.
Corn
This exposure to ultraviolet light—for example, in sunlight— stimulates melanocytes to increase melanin production. The result is a __________________.
Suntan
Although many genes are responsible for skin color, a single mutation can prevent the production of melanin and cause ________________.
Albinism
This is a bluish color to the skin caused by decreased blood O2 content, is an indication of impaired circulatory or respiratory function.
Cyanosis
This is yellowish skin color that can occur when the liver is
damaged by a disease, such as viral hepatitis
Jaundice
This is an injury to a tissue caused by heat, cold, friction, chemicals, electricity, or radiation. And they are classified according to their depth.
Burn
These are Partial-thickness burns;
(1) First-degree burn
(2) Second-degree burn
This is an example of full-degree burn
Third-degree burn
This burn involves only the epidermis and is red
and painful. They can be caused by sunburn or brief exposure to very hot or very cold objects, and they heal without scarring in about a week.
First-degree burn
What is observed in first-degree burns?
Slight edema, or swelling, may be present
This burns damage both the epidermis and
the dermis. Healing takes about 2 weeks, and no scarring results. But if the burn goes deep into the dermis, the wound appears red, tan, or white; can take several months to heal and might scar
Second-degree burns
What is observed in second-degree burns?
If dermal damage is minimal, symptoms include redness, pain, edema, and blisters
These burns damage the complete epidermis and
dermis. The region of this is usually painless because sensory receptors in the epidermis and dermis have been destroyed.
Third-degree burns
What is observed in third-degree burns?
Third-degree burns appear white, tan, brown, black, or deep cherry red.
How do burns heal?
In all second-degree burns, the epidermis, including the stratum Basale, where the stem cells are found, is damaged. The epidermis regenerates from epithelial tissue in hair follicles and sweat glands, as well as from the edges of the wound.
This procedure happens when the epidermis and part of the
dermis are removed from another part of the body and placed over the burn
Split Skin Grafting
This is the most common form of cancer and is triggered by the excessive exposure to UV Rays, wherein fair-skinned people are more prone to it.
Skin Cancer
These UV rays cause tan and is associated with malignant melanomas
UVA
These UV rays cause sunburn
UVB
In this type of cancer, cells in stratum Basale are affected. Moreover, this is a cancer removed by surgery
Basal cell carcinoma:
In this type of cancer, cells above stratum basale are affected and can cause death
Squamous cell carcinoma
In this type of cancer, cancer cells arises from melanocytes in a mole. This is a rare type and can cause death
Malignant melanoma
How is aging and the integumentary system related?
(1) Blood flow decreases and skin becomes thinner due to
decreased amounts of collagen
(2) Decreased activity of sebaceous and sweat glands make
temperature regulation more difficult
(3) Loss of elastic fibers cause skin to sag and wrinkle
