Integumentary System Flashcards
The integumentary system consists of :
the skin and its associated structures,
the hair follicles,
the nails,
the sweat glands, and
the sebaceous (oil) glands
The functions of the integumentary system include:
Protection
Temperature regulation
Sensation
Excretion
Production of vitamin D
It PREVENTS excessive water loss, KEEPS OUT microorganisms that could cause illness, and PROTECTS the underlying tissues from mechanical damage.
PROTECTION
PIGMENTS in the skin called ________ absorb and reflect the sun’s harmful ultraviolet radiation.
melanin
If heat builds up in the body, sweat glands in the skin produce more sweat which evaporates and cools the skin.
REGULATION
when the body _______, blood vessels in the skin EXPAND and bring more blood to the surface, which allows body heat to be LOST.
overheats
If the body is _________, the blood vessels in the skin CONTRACT, resulting in less blood at the body surface, and heat is CONSERVED.
too cold
since sweat removes small amounts of nitrogenous wastes produced by the body.
MINOR EXCRETORY ORGAN
since it contains millions of NERVE ENDINGS that detect touch, heat, cold, pain, and pressure.
SENSE ORGAN
in the presence of SUNLIGHT, and the skin renews and repairs damage to itself.
Vitamin D PRODUCTION
formed by the continuous epithelial membrane, the skin.
Physical Barrier
continuous epithelial membrane
skin
The outermost surface of the skin
epidermis
the epidermis, is covered with __________
dead keratinized cells (stratum corneum).
formed by the production of ACIDIC (low pH) secretions by the oil (sebaceous) glands.
Chemical Barrier
formed by the presence of cells of the immune system within the skin.
Immunological Barrier
These cells function in immunity and disposal of bacteria and viruses by _____________.
“phagocytosis”
a type of cell within the body capable of ENGULFING and ABSORBING BACTERIA and other small cells and particles.
Phagocytes
The nervous system regulates body temperature (through the skin) by ________________.
controlling sweating and dermal blood flow
houses numerous receptors (part of the nervous system) that function in the perception of external stimuli
skin
The skin houses numerous receptors such as
pain
pressure
temperature
free nerve endings
pain
Meissner’s & Pacinian corpuscles for touch and root hair plexuses
pressure
is the formation of WASTE SUBSTANCES (such as sweat and urine) that are REMOVED from the body.
Excretion
TRUE OR FALSE:
Some metabolic wastes, electrolytes, and water are lost by sweating
TRUE
TRUE OR FALSE:
Some metabolic wastes, electrolytes, and water are GAINED by sweating
FALSE
In the presence of sunlight, a sterol (related to cholesterol) is converted to _________
vitamin D3
plays an important role in the intestinal absorption of calcium and regulation of phosphate.
Vitamin D3
The skin consists of two regions
- outer epidermis
- underlying dermis
Underlying the skin (subcutaneous) is a layer called the ____________.
hypodermis
The hypodermis consists mostly of __________
adipose tissue
The hypodermis functions in:
- connecting the skin to underlying structures,
- providing a protective cushion
- providing a source of reserve energy (adipose)
reserve energy
(adipose)
OUTERMOST layer of the skin and is divided into layers according to the structural characteristics of its cells.
Epidermis
Layers of the epidermis
STRATUM CORNEUM
STRATUM LUCIDUM
STRATUM GRANULOSUM
STRATUM SPINOSUM
STRATUM BASALE
The DEEPEST PROTION Of The Epidermis
Stratum Basale
The MOST SUPERFICIAL Portion Of The Epidermis
Stratum Corneum
The cells found in this layer are cuboidal to columnar mitotically active stem cells that are constantly producing keratinocytes for skin repair.
This layer also contains melanocytes.
Stratum Basale
are responsible for the formation of keratin which forms hair, skin and nails
Keratinocytes
characterized by the presence of actively dividing keratinocytes, usually in a single layer.
Stratum Basale
produce melanin responsible for the color of the skin.
melanocytes
prickle cell layer contains irregular, polyhedral cells with cytoplasmic processes, sometimes called “spines”,
Dendritic cells can be found in this layer(help activate the immune system within the body)
Stratum spinosum
located between the deeper stratum basale and the more superficial stratum granulosum.
Stratum Spinosum
function in providing great tensile strength that binds the keratinocytes together.
Desmosomes
Intermediate filaments form a strong intercellular mesh-like cytoskeleton and attach to the numerous cell junctions called ___________________.
desmosomes
Consists of “spiny” prickle cells that interlock to support the skin; thus, the name ______
stratum spinosum.
DIAMOND SHAPED cells with keratohyalin granules and lamellar granules;
Stratum granulosum
contain the GLYCOLIPIDS that get secreted to the surface of the cells and function as a glue, keeping the cells STUCK TOGETHER
lamellar granules
consists of several layers of FLATTENED DEAD CELLS.
This thick layer appears only in frequently used areas such as the palms of the hands and soles of the feet.
Stratum Lucidum
20-30 cell layers
the UPPERMOST layer, made up of keratin and horny scales made up of dead keratinocytes, known as anucleate squamous cells;
varies most in thickness, especially in callused skin;
Stratum corneum
the ____________ secrete DEFENSINS which are part of our first immune defense.
dead keratinocytes
is thick with rows of dead cells.
These cells contain soft keratin, which keeps the skin elastic and protects underlying cells from drying out.
Held together by desmosomes, the keratinocytes provide a protective membrane that resists abrasion and other types of physical trauma.
Stratum Corneum
The _______________ located in the extracellular spaces produces a nearly waterproof barrier.
glycolipids
Cells of the Epidermis
Keratinocytes
Melanocytes
Langerhans cells
Merkel cells
Comprise approximately 90% of all epidermal cells. These cells produce a protein mixture known as KERATIN which helps WATERPROOF AND PROTECT the skin.
Keratinocytes
Comprise approximately 8% of all epidermal cells. These cells produce a group of PIGMENTS known as melanin which are responsible for skin, hair and eye color.
Melanocytes
These cells arise from the bone marrow and migrate to the epidermis. These cells play an important role in the IMMUNE RESPONSE. This helps the immune system by processing ANTIGENS.
Langerhans cells
These cells are in the DEEPEST REGIONS of the epidermis and are associated with SENSORY NEURONS and are thought to function in the sensation of touch. This is involved with TOUCH RECEPTION.
Merkel cells
MOST COMMON cells of the epidermis. provides PROTECTION AND WATERPROOFING SEALANT
KERATINOCYTES
produces and transfer the protein melanin to keratinocytes
MELANOCYTES
a brown/black pigment that ABSORBS UV-LIGHT
MELANIN
This is known as the “TRUE SKIN,” this is the layer beneath the epidermis.
Dermis
major parts of the dermis:
Collagen
Reticular Fibers
Elastic Fibers
a protein that adds strength
Collagen
thin protein that add support
Reticular Fibers
a protein that adds flexibility
Elastic Fibers
two layers of dermis
Reticular layer
Papillary layer
this contains CRISSCROSSING collagen fibers that form a STRONG ELASTIC NETWORK
Reticular layer
This network forms a pattern called ___________________.
cleavage lines or the Langer’s lines
also contains Pacinian corpuscles, sensory receptors for deep pressure/ TOUCH pressure
reticular layer
This layer contains sweat glands, lymph vessels, smooth muscle, and hair follicles.
reticular layer
this layer lies directly beneath the epidermis and connects to it through papillae (finger-like projections).
is what gives you FINGERPRINTS.
Papillary layer
are especially effective at transmitting information about MOVEMENT between the skin and another surface.
This can be used to sense texture and to detect if an object is sliding past the skin—which is important for maintaining GRIP
Meissner’s corpuscles
also known as the SUBCUTANEOUS tissue that attaches the skin to underlying bones and muscles and supplies it with blood vessels and nerves.
consists mostly of connective tissue and adipose cells.
Hypodermis
TRUE OR FALSE:
As much as one half of the body’s stored fat is in the hypodermis
TRUE
TRUE OR FALSE:
As much as one half of the body’s stored fat is in the skin
FALSE
develops from the EMBRYONIC EPIDERMIS and its primary function is PROTECTION.
HAIR
A hair is divided into:
shaft and root
the aspect of the hair that PROTRUDES ABOVE THE SURFACE OF THE SKIN
shaft
is the aspect of the hair that is BENEATH the surface of the skin.
root
Base of the root is known as the _____________
hair bulb
A hair is composed of numerous columns of dead yet keratinized cells held tightly together in three concentric layers known as the ______________.
medulla, cortex and cuticle
are plates of hard, tightly packed keratinized cells of epidermis.
allow us to grasp and manipulate small objects.
NAILS
3 PARTS of the NAILS
Nail body
Free edge-
Nail root
The visible portion of the nail.
Nail body
The aspect of the nail that may extend past the distal end of the digit.
Free edge-
The aspect of the nail that is buried underneath a fold of skin.
Nail root
The whitish semilunar area of the proximal end of the nail body.
Lanula
Also known as the cuticle. This is a narrow band of epidermis which extends from the lateral border of the nail wall.
Epychonium
Epithelial tissue deep to the nail root where actual nail growth occurs
Nail matrix
The two major glands of the integumentary system
sebaceous and sweat glands
located in the dermis and are usually connected to hair follicles.
Sebaceous glands
Sebaceous glands produce an oily, white substance known as __________ which oils the hair and skin and thus prevents drying and also provides protection against some bacteria
sebum
Sweat glands – are divided into two types
eccrine and apocrine sweat glands
also known as merocrine sweat glands, are the most common type of sweat glands.
Eccrine sweat glands
These sweat glands are composed of simple coiled tubular glands that open directly onto the surface of the skin through sweat pores.
These glands are most numerous on the palms of the hands & the soles of the feet.
Eccrine sweat glands
are composed of compound coiled tubular glands that usually open into hair follicles superficial to the opening of sebaceous glands.
apocrine sweat glands
excrete sweat to regulate temperature
Sweat Glands ( sudoriferous glands)
oil-producing glands that keep skin and hair moist and soft
Sebaceous glands
glands of the ear canal that produce earwax
Ceruminous glands
Types of cutaneous glands
Sweat Glands ( sudoriferous glands)
Sebaceous glands
Ceruminous glands
Mammary glands
Lacrimal glands
milk-producing glands located in the breasts
Mammary glands
produce tears to moisten eyes
Lacrimal glands
The MOST SUPERFICIAL section of skin, made up of epithelial tissue
Epidermis
Below the epidermis, and above the hypodermis, this section of skin contains MANY STRUCTURES including blood vessels
Dermis
The layer of tissue below the dermis, made up mostly of FAT
Hypodermis
These CARRY BLOOD BACK to the heart
Vein
These CARRY BLOOD AWAY from the heart
Artery
This gland is connected to the hair follicle, and SECRETES SWEAT THAT SMELLS BAD
Apocrine sweat glands
This muscle contracts to STAND the hair up
Arrector pili muscle
These CARRY information to and from the brain
nerve
The BASE of the hair within the dermis
Hair root
This gland secretes SEBUM, or oil, onto the hair
Sebaceous glands
This gland can be found all over the body, and secretes sweat that does NOT smell bad.
Eccrine sweat glands
The DEEPEST layer of the epidermis, made up of living simple cuboidal cells
Stratum Basale
The most superficial layer of the epidermis, made up of many layers of DEAD squamous cells
Stratum corneum
