Integumentary System Flashcards
What is a hair shaft?
The actual tube of hair. All the cells of the shaft are dead
What is an Arrector pili
A small muscle located parallel to hair follicle. Looks like a string
Sebaceous gland
A gland next to a hair follicle that secretes sebum. Looks like a weird face from side veiw
What is a hair root?
The part of the hair that contains both the cuticle, cortex, medulla and the hair matrix, dermal papilla, and melanocytes
Hair bulb
The hair bulb contains the dermal papilla, melanocytes and the hair matrix
What is the medulla?
The inner most layer of the hair. Contains air pockets and large cells
What is the cortex
The layer of the hair that is intermediate the medulla and cuticle. Contains melanin, hair color
What is the cuticle?
The outermost layer of the hair. Keratinized
What is the internal root sheath?
It lairs out side the cuticle. In the follicle.
What is the external root sheath?
Lies out side the internal root sheath in the hair follicle. Sometimes called the epithelial root sheath
What is the glassy membrane?
Membrane that lies out side of the external tooth sheath.
What is the peripheral CT?
Also known as the fibrous sheath. It lies outside of the glassy membrane. It’s the outer most layer
What is the follicle wall?
Consists of the internal root sheath all the way to the peripheral CT. Parts of the follicle that do not involve the hair itself.
What is the hair matrix?
The area of the hair bulb that produces the hair. On top of the dermal papilla
What is the dermal papilla?
The little nub of dermis that supplies the hair matrix with nutrients.
What is a melanocyte?
A cell found on the lateral sides of the dermal papilla responsible for giving hair color. Looks like moose antlers
Where does the hair follicle start?
The dermis
Hairs act as..
Sensitive touch receptors
Hairs are called..
Pili
The only live part of the hair is.
The matrix
The epidermis is composed of what layers?
- Stratum basale
- Stratum spinosum
- Stratum granulosum
- Stratum lucidum (thick skin)
- Stratum cornea
Stratum basale
Where cells are produced
Stratum spinosum
Spiny-cells, keratinization starts here
Stratum granulosum
Flat cells, visible keratin granules. Cells are starting to die
Stratum lucidum
Only found in thick skin. Clear layer
Stratum corneum
“Horny layer” the outer most layer of scales. Completely dead and keratinized
The skin is composed of..
- the epidermis
- the dermis
What are the layers of the dermis?
- Reticular layer
2. Papillary layer
Hypodermis
Not part of the skin, beneath the dermis, composed of adipose tissue; which anchors the skin, protects from infection and insulates.
What type of et tissue is the epidermis?
Stratified Squamous et
The dermis is
Strong flexible connective tissue; like a hide… The Suade part of leather
The reticular layer of the dermis is made of DICT
The reticular layer
Cleavage lines
Where collagen and elastic fibers run parallel. Incisions made parallel heal better
Flexure lines
Form where dermis is closely attached to underlying fascia
Friction ridges
Found on fingertip, have sweat gland that make finger prints. Pattern is caused dermal ridges. Enhance gripping abilities
The dermis supplies the nutrients and blood to what?
The epidermis
Melanocyte
Makes melanin, found in stratum basale near dermis
Tactile cell
Found in stratum basale near dermis, it has a sensory nerve ending which extends into the dermis
Dendritic cell
Found in stratum spinosum. Has to do withy me system
The cells of the epidermis have what kind of junctions?
Tight and desmosome
Nervous structures
- sensory nerve fiber; branching nerve
- lamellar corpuscle; spiral
- root plexus; branched around root
Cutaneous plexus
Blood vessels in the dermis
Eccrine sweat gland
Coily bundle
Arrector pili muscle
Little muscle attached to hair. Pulls on hair
Sebaceous oil gland
Little sacs attached to hair follicle which release sebum (oil)
Hair follicle
Hole where hair grows out
Hair root
The very base of the hair follicle.
Dermal papillae
Little nipple things on top of dermis
Sweat pore
Where sweat exits the eccrine sweat gland
Sub papillary plexus
Blood vessels found in papillae
Skin is what percent of body weight in adult?
7%
Adenoma
Tumor of the glandular epithelium
Autopsy
Postmortem examin. Necropsy
Carcinoma
Cancer arising in the epithelium accounts for 90% of human cancers
Healing by first intention
Clean wound. Suture
Healing by second intention
Messy wound. Unattended healing
Keloid
Proliferation of CT during healing of skin wounds
Lesion
A injury or wound that tissue over a defined area
Marfan’s syndrome
Genetic disease, lack of fibrillin in elastic fibers. Loos joints, weakens blood vessles, spider hands, vision probs.
Osteogenesis imperfecta
Aka brittle bone disease. Defective collagen production which translates into weak bones which fracture easily
Pathology
Scientific study of the affects of disease on the body’s organs and tissues
Pus
A collection of tissue fluid containing white blood cells, bacteria, dead and dying tissue cells and macrophages in an inflamed area
Sarcoma
Cancer arising in CT and Muscle tissue
Scurvy
A disease caused by lack of vitamin C needed to make collagen. Causes tooth loss, delay in wound healing, weak scar tissue
VAC
Vacuum assisted closure. An innovative healing process where a sponge is put over the wound and a vacuum is placed over the sponge. Induces healing when all other methods fail. Prompts fibroblasts to create collagen
What type of hair is found on children and adult women?
Vellus hair, this type of hair is usually fine and colorless.
What is the thick dark hair on the scalp, eyebrows and pubic region called?
Terminal hair
What are the 2 types of hair?
Terminal and Vellus
The condition in which females grow excessive hair.
Hirsutism
What are the growth cycles of a hair?
- active phase
- regressive phase
- resting phase
Active phase of hair
Hair is actively growing, can last weeks or years
Regressive phase of hair cycle
The hair matrix cells die
Resting phase of hair cycle
Lasts 1-3 months, after this phase matrix regenerates sand hair grows again.
How long can hair follicles remain active?
6-10 years
How come eyebrow hairs do not reach the length of scalp hairs?
Because the follicles of the eyebrow hairs only remain active for 3-4 months
Alopecia
Balding
When some one loses terminal hair what happens?
Terminal hairs are replaced with Vellus hairs or the growth cycle becomes so short hairs do not emerge
Male pattern baldness
A genetically determined, sex influences condition. Possibly caused by a delay action gene that turns on in adulthood and changes hair follicles response to DHT
Finasteride or propecia
A medication for male pattern hair loss
What are outstanding examples of some of the reasons why a person may lose hair?
- Acutely high fever
- surgery
- severe emotional trauma
- certain drugs
- too much vitamin A
- antidepressants
- blood thinners
- anabolic steroids
- chemo therapy drugs
- protein deficient diets
- lactation
In most cases hair that is lost can be regrowing except for?
Follicles that have be destroyed or damaged.
What is a nail?
A scale -like modification of the epidermis that forms a clear protective covering on the dorsal surface of the distal part of the finger or toe
Nails and hair contain what kind of keratin? What kind of keratin does skin contain?
The epidermis contains soft keratin, while nails and hair contain hard keratin.
What does each nail have?
- free edge
- a nail plate or body (visible attached portion)
- proximal root (embedded in the skin)
The nail bed
The deeper layers of the epidermis extend beneath the nail as the nail bed.
The nail matrix
He thickened proximal portion of the nail bed responsible for nail growth.
How does the nail grow?
As nail cells produced by the matrix become heavily keratinized, the nail body slides dis tally over the nail bed
What is the lunule?
The white crescent laying over the nail matrix
The proximal an lateral borders of the nails are overlapped by…
Skin folds, called nail folds
Eponychium
The cuticle, proximal nail fold which projects onto the nail body
Hyponychoim
The thickened region beneath the free edge of the nail where dirt and debris tend to accumulate. Informally called the quick. It secure the free edge of the nail to the finger tip
Yellow tinged nails may indicate?
Respiratory or thyroid gland disorder
Thick yellow nails may signal
A fungus infection
An outward concavity of the nail (spoon nail) may signal …
An iron deficiency
Horizontal lines on the nails
Called beaus lines, may indicate malnutrition
A sweat gland is called a
Sudoriferous gland
Sudoriferous gland are not found where?
Nipples and parts of the external genitalia
The 2 types of sudoriferous glands.
- eccrine
- apocrine
Myoepithelial cells
Specialized cells that contract when stimulated by the nervous system. Their contraction forces the sweat into and through the gland’s duct system to the skin’a surface
Eccrine sweat glands are also known as…
Merocrine sweat glands
Where are eccrine glands found abundantly?
- the palms
- soles of feet
- the forehead
Structure of eccrine gland
A simple, coiled, tubular gland. The secretory part lies coiled in the dermis, and the duct extends to open in a funnel shaped pore at the skins surface
The difference between sweat pores and pores on face.
The pores on a person’s face are associated with hair follicles
Sweat is..
Eccrine gland secretion that is a hypotonic filtrate of the blood that pass through the secretory cells of the sweat glands and is released by exocytosis
What is in sweat?
- 99% water
- some salts (sodium chloride)
- vitamin C
- antibodies
- anti microbial substances
- traces of metabolic wastes
- urea
- Uric acid
- ammonia
- small amounts of ingested drugs
- the exact composition depends on Heredity and diet
Sweat has a ph between 4 and 6 which makes it
Acidic
What regulates sweating?
The autonomic nervous system
What is the purpose of sweating?
To prevent the body from overheating
Where does heat induces sweating begin?
- it begins on the forehead and spreads inferiorly over the remainder of the body
Where does emotionally induced sweating start?
Begins on the palms, soles and axillae, and then spreads to other body areas
Apocrine sweat glands are found where?
The axillary and anogenital areas
Apocrine gland are
Larger than eccrine glands and are found in the dermis or even hypodermis. Their ducts empty into hair follicles
The difference between apocrine secretions and eccrine secretions
Apocrine sweat contains added fatty substances and proteins
Apocrine sweat appears
Viscous, milky or yellowish
The decomposition of apocrine sweat by bacteria creates what and contributes to what
A musky odor which is the basis for B.O.
A procedure glands begin functioning
In puberty, under the influence of androgens
Role of apocrine glands
They do not control body temp. They may be the human equivalent of other animals’ sexual scent glands
Ceruminous glands
Modified apocrine glands found in the painting of the external ear canal. Their secretion mixes with sebum to create cerumen or ear wax
Cerumen’s Role
To deter insects and block entry of foreign material
Mammary glands
A specialized sweat gland that secretes milk
Sebaceous glands
Simple branched alveolar glands that are found all over the body except thick skin
Sebaceous glands make what
Sebum; a greasy substance
Sebaceous glands are what type of glands and why
Holocrine glands because the glands build up substance until they Burt and release their product
Sebaceous glands are attached to a hair but some can be free
True a sebaceous gland can be attached to a hair or have a pore on the skin surface
Functions of sebum
- softens and lubricates hair and skin
- prevents hair from becoming brittle
- slows water loss from the skin when external humidity is low
- bactericidal
What is arrector pili’s roll in sebum distribution?
Arrector pili muscles contract to force sebum out
Sebum secretions is affected by
Androgen production
Acne
An active inflammation of the sebaceous glands accompanied by pimples, on the skin. Usually cased by staph infection, (bacterial)
Function of the integumentary system
Protection, body temperature regulation, cutaneous sensation, metabolic functions, blood reservoir, excretion
He skin is a barrier to what 3 things
Chemical, physical and biological
How does the skin chemically block things
The acid mantle retards bacteria growth. Skin cells secrete natural antibiotics. Melanin blocks UV rays
How does the skin act as a physical barrier.
The continuity of the skin and hardiness of the keratinized cells provide a physical barrier
The affect of alcoholic drinks on skin permeability
Alcohol increases permeability of the skin at least 24 hours after ingestion
Substances the penetrate the skin in limited amounts
Lipid soluble substances- O2, CO2, fat soluble vitamins (A,D, E and K) steroids (estrogens)
Oleoresins of poison ivy and oak
Organic solvents, such as acetone,paint thinner (desolve cell lipids)
Heavy metal salts (lead and mercury)
Some drugs, nitroglycerine, and nicotine
Penetration enhancers which help ferry other drugs into the body
The biological barrier of the skin includes what?
Biological barriers of the skin include dendritic cells of the epidermis, macrophages in the dermis and DNA itself
When it is cold and blood vessels in the skin contract
Blood flow bypasses skin, allowing skin to cool down as a result slows down passive heat loss
Cutaneous sensory receptors
Are actually part of the nervous system. Extroceptors pick up stimuli from outside environment w
Metabolic functions of integumentary system
Skin aids in the production of vitamin D. Keratinocyte enzymes can disarm cancer causing chems. That penetrate the epidermis, activate steroid hormones, can turn cortisone applied to the skin into hydrocortisone
The function of the skin as a blood reservoir
Dermal vascular supply is extensive and can hold up to 5% of the entire body’s blood volume. When other organs need blood, the nervous system constricts the dermal blood vessels allowing more blood to become available
He function of the integumentary system and excretion
The body eliminates limited amts. of nitrogenous wastes in sweat
How many Americans develop skin cancer at one point?
One in 5
What is the single most important factor in the development of skin cancer?
Overexposure to UV radiation in sunlight which damages DNA bases
What causes skin to peel in a sunburn
Fas a protein that causes genetically damaged skin cells to commit suicide to keep damaged cells from proliferating
The three major forms of skin cancer
Basal cell carcinoma
Squamous cell carcinoma
Melanoma
Basal cell carcinoma
He least malignant and most common cancer. Pearly node with ulcer in the middle, originates in stratum basale, rarely metastasizes, grows slow, easily cured
Squamous cell carcinoma
Second most common skin cancer, arises from keratinocytes in the stratum spinosum. Lesion appears as a scaly red papule, found mostly on the head. Grows rapidly and metastasizes if not removed. If caught early and removed the chances of complete cure is good
Melanoma
Cancer of the melanocytes, the most dangerous type of skin cancer; because it is highly metastatic and resistors chemotherapy. Only 2-3% of skin cancers are melanoma. Melanoma can begin wherever there is pigment. Looks like a fast growing black-brown patch;1/3 evolve from preexisting moles. Early detection is key to survival
ABCD rule for recognizing melanoma
Asemmetry- two sides of mole do not match
Border irregularity- the borders of the lesion exhibit indentations
Color- the pigmented spot has more than one color
Diameter- the spot is larger than 6mm in diameter (size of pencil eraser)
(Sometimes E) for elevation above skin surface
Definition of a burn
A tissue damage inflicted by intense heat, electricity, radiation or certain chemicals.
The immediate threat to life resulting from burns is
A catastrophic loss of body fluids containing proteins and electrolytes. This leads to dehydration and electrolyte imbalance, renal failure, and circulatory shock. Fluids must be replaced by IV to save the patient’s life
Rule of nines
In adults, the volume of fluid lost can be estimated by computing the percentage of body surface burned. This method divides the body into 11 areas
In addition to IV fluids burn patients need…
Thousands of extra calories a day to replace proteins and allow tissue repair. Burn patients are given supplementary nutrients through gastric tubes and IV lines
In the case of a burn, after the initial crisis has passed what becomes the main threat
Infection and sepsis. Burned skin is sterile for 24 hours. Afterward it it vulnerable, and pathogens easily invade damaged skin.
First degree burns
Only epidermis is damaged. Symptoms include localized redness, swelling and pain. Heals well on its own
Second degree burns
Injure the epidermis and he upper region of the dermis. Symptoms are similar to first degree burns, but also include blisters. Scaring is not likely if care is taken and infection is avoided
First and second degree burns are known as
Partial thickness burns
Third degree burn
Known as a full thickness burn. It involves the entire thickness of the skin. Burned area appears, grey-white, cherry red or blackened. Since nerve endings are destroyed no pain. Skin can regrowing but not fast enough skin grafting is advised
Burns are considered critical when
25% of the body has 2nd degree burns
10% of the body has 3rd degree burns
3rd degree burns of the face, hands or feet
Why are burns at joints troublesome?
Scar tissue can severely limit joint mobility
Why are facial burns troublesome?
Facial burns can mean burned respiratory passage ways, which could be swollen and lead to suffocation
Treatment of burns
Burns are debrieded, flooded with antibiotics and then covered with a graft or membrane
Albinism
Inherited condition in which melanocytes do not produce pigment
Boils and carbuncles
Inflammation of hair follicles and sebaceous glands in which an infection has spread to the hypodermis. Common on dorsal neck. Carbuncles are composite boils, common cause is bacterial infection
Cold sores (fever blisters)
Small fluid filled blisters that itch and hurt. Found around the mouth and in mucosa of mouth.caused by herpes simplex infection. Can be activated by emotional upset, fever, or UV radiation
Contact dermatitis
Itching, redness, and swelling, progressing to blister formation, caused by exposure to chems. That provoke allergic reaction
Decubitus ulcer
Localized breakdown and ulceration of skin due to interference with its blood supply. Usually occurs over a boney prominence, such as a hip or heel, that is subjected to continuous pressure; also called a bed sore
Dermatology
The branch of medicine that studies and treats disorders of the skin
Eczema
A skin rash that itches, blisters and oozes, the skin also scales. A common allergic reaction in children, but also occurs (typically in a more) in adults. Frequent causes include allergic reactions to certain foods or inhaled dust or pollen. Treated by methods used for other allergic disorders
Epidermolysis
A group of hereditary disorders characterized by inadequate or faulty synthesis of keratin, collagen, and or basement membrane “cement” that results in lack of cohesion between layers of the skin and mucosa. A simple touch causes layers to separate and blister. For this reason be victims are called touch me nots. In severe cases fatal blistering occurs in major vital organs. Blisters rupture and can cause infection, infections occur often
