Integumentary System Flashcards
What does the integumentary system consist of
Skin hair, nails, glands and claws
Define dermatology
Studies structure and function of disorders of the integument
What is the largest organ of the body weighing about 10 lb
The integumentary system
What is the epidermis?
The superficial layer of the skin
What type of cells is the epidermis made of?
Keratinized stratified squamous
What are keratinocytes?
Cells that produce the waterproofing material keratin
Found in the epidermis
What is a melanocyte?
A cell that produces melanin which makes your skin tone
Found in the epidermis
What are langerhans cells?
Immune cells in the epidermis
What is thin skin versus thick skin?
Thin skin comprises most of the skin and has four layers
Thick skin is found on the palms and soles and has five layers
What are the five layers of the epidermis
Stratum basale
Stratham spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum
What is the stratum basal layer of the epidermis constantly undergoing
Mitosis
What is the stratum basal layer made of?
A single row of keratinocytes
In the stratum basal layer keratin filaments form what?
Desmosomes which anchor to adjacent cells
What are hemidesmosomes in the stratum basal layer?
They attached the epithelial cells to the underlying connective tissue
What are the features of the stratum spinosum?
It looks spiny and is pushed up from the stratum basal layer
How many layers are there in the stratum spinosum and what are the features of the cells?
It is 8 to 10 layers thick
Cells in the layer are starting to shrink, but the desmosomes remain intact
This makes the cells look spiny under the microscope
What epidermis layer holds langerhans cells?
The stratum spinosum
What are the features of the stratum granulosum layer?
Three to five layers of cells undergoing apoptosis
Define apoptosis
programmed cell death
What happens to the organelles of the stratum granulosum?
The organelles begin to degenerate as cells are pushed up and away from their blood supply
In which layer are the lamellar granules located?
And what are they
They are located in the stratum granulosum
They are visible as cells degenerate the granules secrete a lipid substance between the cell walls, creating a water repellent layer and reducing water loss
They look like sand granules
What are the functions of desmosomes?
They hold the cells together
In what layer of the epidermis do cells die?
stratom granulosum
What type of skin is stratum lucidum found on?
It is only found on The palms, soles and digits of thick skin
How many layers of cells is the stratum lucidum composed of and what does it contain?
4 to 6 layers of dead cells
And it contains a large amount of keratin
How many layers are there in the stratom corneum and what does it protect
It is composed of 25 to 30 layers of dead keratinocytes
It protects underlying tissues and prevents microbial invasion
What is a callus
Thickening of the skin due to friction
It becomes thick because a lot of mitosis is going on
What happens during keratinization?
Cells are pushed from the basal layer and they accumulate more and more keratin
What happens to epidermal cells 7 to 10 weeks after they are formed
They reached the surface of the epidermis
What is the epidermal growth factor or EGF
It is a hormone-like substance that stimulates mitosis when skin is damaged
What is dandruff?
Excessive shedding of scalp cells
Comes from a fungal infection
What is the dermis made of?
Dense irregular connective tissue which contains collagen and elastic fibers
What are the features of the dermis and what does it contain?
It resists pulling in multiple directions
It is thicker than the epidermis
It contains blood vessels, nerves glands and hair follicles
Where do the ridges in the papillary dermis extend up into
The epidermis
What are dermal papillae?
Ridges in the dermis that extend up into the epidermis
You know them as your fingerprints
They are there for gripping
And they are different in everyone including twins
What is the reticular dermis made of
Bundles of collagen fibers, fibroblasts and macrophages
What happens when collagen fibers break?
It causes wrinkles or stretch marks
What are other names for the hypodermis?
Subcutaneous or Sub-Q hypodermis
What type of tissue does the hypodermis consist of?
Areolar and adipose
Fibers from the hypoepidermis anchor it to what?
Muscles
What does the hypoepidermis store?
Adipose between the strings of the areolar connective tissue
As adipose puffs up, you get cellulite
What structures are located in the hypodermis
Adipose storage
Nerve endings
Blood vessels
Pressure receptors
What are pacinian corpuscles?
Pressure receptors in the hypodermis
What are melanocytes?
cells that produce melanin which ranges from yellow to black
What is pheomalanin
Yellow to red melanin pigment
What is eumelanin
Brown to black melanin pigment
If everyone has about the same number of melanocytes, why do people have different skin tone colors
The melanocyte cells produce different amounts of pigment based on genetics and the amount of pigment produced determines the skin tone
What are freckles and can they cause cancer
They are clusters of melanin
You have a genetic predisposition for them, meaning you may or may not get them, but they cannot cause cancer
What is a Nevis
An overgrowth of melanocytes
Also known as a mole
What causes melanin production to increase and what is it trying to protect?
Uv light
In order to protect the DNA and cells
Melon informs an umbrella of protection over the nuclei
How does the enzyme tyrosinase affect melanin production and what happens if you cannot produce it?
The enzyme tyrosinase is made from the amino acid tyrosine
If a person is unable to make the enzyme tyrosine, they will have no pigment
Meaning albinism
This makes them really susceptible to skin cancer
What is vitiligo caused by
The destruction of melanocytes in patches
It is an autoimmune disease
What is hemoglobin and? Who is it common in?
It is red pigment in the blood that carries oxygen
It is common in those that have fair skin due to low melanin production
The red vessels in the dermis give the skin a pink tone
What is carotene and where is it found
It is a yellow orange pigment found in the fatty areas of the dermis
Where do you find carotene in your diet
Yellow and orange fruits and vegetables
What culture of people naturally has carotene?
Those of Asian descent
What happens in your tissues after ingesting high amounts of carotene?
It can accumulate in your tissues giving you an orange color
What is carotene important for
Vision beta-carotene forms vitamin a which is necessary for eyesight
What are the four diagnostic skin colors
Cyanotic
Jaundice
Erythema
Pallor
What is cyanotic skin color look like and what is it caused by?
A lack of oxygen and it’s a blue color
What is jaundice skin color look like and what does it cost by
A buildup of bilirubin and the skin and eyes and it is a yellow color
What is erythema skin color look like? And What is it caused by?
Vasodilation causes skin to appear red
Caused by
High body temperature
Allergic reactions
Inflammation
Infection
Fever
What is pyrexia
Fever
What is pallor skin color caused by and what does it look like
It is a chalky color of the skin
It is caused by anemia
Shock
Frostbite
In individuals with darker skin tones, you check your nail beds for the chalky color
Hair is found on all surfaces except for what?
The nipples palms soles palmar surfaces of fingers
What is the function of hair
Protection and sensory reception( tickle sensation)
What is the shaft of the hair
It projects above the skin surface (visible portion)
What is the cuticle of the hair refer to?
It refers to the outer covering of cells that overlay one another like shingles
The overlapping pattern determines species
What is the follicle of the hair made of and what is its location
It is made of epithelial cells
It surrounds the root of the hair in the dermis
What does each growing hair have?
A blood supply
Oil gland
A smooth muscle supply called the arrector muscle
A nerve supply called the hair root plexus
What is the arrector muscle?
The smooth muscle of the hair
Another name is arrector pilli
What is the hair root? Plexus
The nerve supply of the hair
Where is the matrix of the hair located and what is it
It is located in the dermis
It is an area of active growth
Meaning new cells get pushed upward and die
What is alopecia?
Complete or partial lack of hair
Determined by Mom’s genetics
What is gray hair?
When you have minimal amounts of melanin
What is white hair?
When you have air bubbles in the shaft
What does the sebaceous gland help lubricate and what is it
It is an oil gland that helps lubricate the hair and skin
Define sebum and what is it made out of?
Oil
It is made from triglycerides, cholesterol and proteins
What are secretory cells
And where are they and where are they not?
They are cells thay lay in the dermis and empty into hair follicles
They are absent on the palms, soles and lateral surfaces of fingers
What do sebaceous glands lubricate?
They lubricate the hair and skin
Reducing water loss
And inhibiting growth of some microbes
What is acne?
Inflammation of the sebaceous gland due to the overproduction of sex, hormones, estrogen and testosterone
What is cystic acne
Connective tissue sac forms at the gland
forms of scar
The treatment is harsh for it
What are your suedoriferous glands and what do they empty into
Your sweat glands
They empty into hair follicles or onto body surfaces
What are the three types of pigment that color your skin
Melanin
Hemoglobin
Carotene
What are the two Sudoriferous glands?
Eccrine
Apocrine
What are the features of the eccrine gland?
It covers most of the body
It’s most numerous on the forehead
And decreases as you go down the body
It empties onto body surfaces through pores
What substances does the eccrine gland secrete
Water
Ions
Uric acid
Ammonia
Lactic acid
When does the eccrine gland start functioning and what is its function
It begins functioning at birth
Its function is thermal regulation through evaporation and emotional sweating when stressed
Where is the apocrine gland found?
It is found in the axilla. (Armpits) Groin areola and bearded regions of a man’s face
It empties into the hair follicles of these areas
What does the aprocrin gland have to do with reproduction
It produces pheromones to try and find a mate
What does the apocrine gland secrete
Similar components to the ECCrine gland with lipids and proteins, which bacteria on the skin like to metabolize this creates an odor
It does contain more proteins than the eccrine gland
When does the apocrine gland begin to function?
At puberty
What is the dormitory effect?
You start menstruating at the same time as other women who work closely with you or live with you
In men, the dormitory effect works with beard growth
What is the function and location of ceruminous glands?
They are located in the external auditory meatud or ear canal
They secrete cerumen which provides a barrier to prevent the entrance of foreign material
Define cerumen
Ear wax
Is it visible part of the nail alive or dead
It is dead
What is the nail? Plate( body)
It is the visible nail
It is pink due to vascularization
What is the free edge of the nail
It extends beyond the tip of the finger
It is white due to lack of vessels
What is the lunula?
It is a half moon shaped structure at the back of the nail. It is the thickest part
What is the matrix of the nail?
It is an area of active growth at the base of the nail. New cells are pushed, forward and die
It is high in keratin which makes them strong
What is the function of the nails
Protection of digits
Enhanced touch perception
Allow us to grasp and manipulate things
Scratches itches
When do signs of aging begin
Around age 40
What happens to college and fibers during aging
They decrease in number and break
What happens to elastic fibers during aging
What happens to elastic fibers during aging? They lose elasticity
This is accelerated in smokers by double
What happens to fibroblasts with aging?
They decrease an amount which allows wrinkles to develop
What happens to sweat with aging?
There’s a decrease in sweat production which increases the risk of heat stroke
What happens to hair loss with aging
It increases in both men and women
With blonde hair you lose about a hundred hairs a day
With dark hair you lose about 70 hairs a day
When do age spots develop and growth of hair and nails slow
Around age 40 40
