CHAPTER 2: Skin and Body Membranes Flashcards
Two types of body membranes
- Epithelial Membranes
- Connective Tissue Membrane
covering and lining membranes
epithelial membranes
- The epithelial membranes, also called covering and lining membranes, include the (3)
-cutaneous membrane (skin)
-mucous membranes
-serous membranes
The cutaneous membrane is composed of two
layers,
-superficial epidermis
-underlying dermis
superficial epidermis composed of
squamous epithelial tissue
underlying dermis is composed of
dense irregular connective tissues
A mucous membrane (mucosa) is composed of epithelium resting on a loose (areolar) connective tissue membrane called a
lamina propria
A mucous membrane (mucosa) is composed of epithelium resting on a __________ called a lamina propria.
loose (areolar) connective tissue membrane
This membrane type lines all body cavities that open to the exterior.
mucous membrane (mucosa)
The epithelium of mucosae is often adapted for __ or ___.
absorption or secretion.
is composed of a layer of simple squamous epithelium resting on a thin layer of areolar connective tissue
Serous Membrane or Serosa
Serous membrane or serosa is composed of a layer of ____ areolar connective tissue
simple squamous epithelium
Serous membranes folds in on itself to form the ____ which covers the outside of the organ(s) in that
cavity.
visceral layer
Serous membrane contains _____ allows the organs to slide easily across the cavity walls and one another without friction or pain as they carry out their routine functions
serous fluids
These membranes line the fibrous capsules surrounding joints providing a smooth surface
and secreting lubricating fluid.
Connective tissue membranes
composed of loose areolar connective tissue and contain no epithelial cells at all.
Synovial membranes
Synovial membranes composed of ____ and contain no _____at all.
-loose areolar connective tissue
-epithelial
small sacs of connective tissue
bursae
line and cushion organs moving
against each other during muscle activity— such as the movement of a tendon across a bone’s surface
-bursae
-tendon sheaths
Functions of the Integumentary System
- Mechanical Damage
- Chemical Damage
- Microbe Damage
- Ultraviolet (UV) radiation
- Thermal Damage
- Desiccation (drying our)
- Aids in body temp reg
- Aids in excretion of urea and uric acid
- Synthesized Vit D
-Physical barrier contains keratin, which toughens cells
-pressure and pain receptors, which alert the nervous system to possible damage.
Mechanical damage
alert the nervous system to possible damage
pressure and pain receptors
Has impermeable keratinized cells; contains pain receptor, which alert the nervous system for possible damage
Chemical Damage
Has an unbroken surface and
“acid mantle”. (skin secretions are acidic and thus inhibit microbes such as bacteria and yeast). Phagocytes ingest foreign substances and pathogens, preventing them from penetrating into deep body tissues.
Microbe Damage
Melanin produced by melanocytes protects DNA from UV damage.
Ultraviolet (UV) radiation
Skin contains heat/cold/pain
receptors.
Thermal Damage
Contains a water resistant glycolipid and keratin.
Desiccation (drying out)
Heat loss: Activating sweat glands and by allowing blood to flush into skin capillary beds so that heat
can radiate from skin surface.
Heat Retention: By not allowing blood to flush into skin, capillary beds.
Aids in body temperature regulation
Activating sweat glands and by allowing blood to flush into skin capillary beds so that heat
can radiate from skin surface.
Heat loss
By not allowing blood to flush into skin, capillary beds.
Heat Retention
Contained in perspiration produced by sweat glands.
Aids in excretion of urea and uric acid
Modified cholesterol molecules in skin converted to vitamin D in the presence of sunlight.
Synthesized Vitamin D
_____ molecules in skin converted to vitamin D in the presence of sunlight.
Modified cholesterol
Structure of Skin (3)
-Epidermis
-Dermis
-Hypodermis
is made up of stratified
squamous epithelium that is capable of becoming
hard and tough.
epidermis
Made up of
-Epidermis
-Dermis
-Hypodermis
Epidermis- stratified squamous epithelium
Dermis-dense irregular connective tissue
Hypodermis-adipose (fat) tissue
not considered part of the skin, but it does anchor the skin to underlying organs and provides a site for nutrient storage.
Hypodermis
Layers of Dermis
Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Dermis
Cells are dead, membranous
sacs filled with keratin.
Stratum corneum
Cells begin to die.
Stratum lucidum
Cells are flattened, organelles are deteriorating, cytoplasm full of granules.
Stratum granulosum
Cells contain thick bundles of
intermediate filaments made of pre-keratin.
Stratum spinosum
Stem cells are actively dividing;
some newly formed cells become part of more superficial layers.
Stratum basale
Cells found in the Epidermis (5)
-Keratinocytes
-Melanocytes
-Langerhans Cells
-Merkel Cells
-Basal Cells
Specialized cells that produce
keratin
-Keratinocytes
Specialized cells that produce
melanin
-Melanocytes
are immune system cells that
detect and fight pathogens entering the skin
-Langerhans Cells
sensory cells that respond to light
touch and connect to nerve endings in the dermis
-Merkel Cells
is a strong, stretch envelope that helps to bind the body together.
dermis
The connective tissue making up the dermis consists of two major regions/ Layers of Dermis
-papillary
-reticular areas
Made up of
-papillary
-reticular areas
papillary- areolar
reticular areas- dense irregular connective tissue
The papillary layer is the superficial dermal region that contain called
dermal papillae
house pain receptors (free nerve endings) and touch receptors.
papillary dermis
- On the palms of the hands and soles of the feet, the papillae are arranged in ___ that form ___ and _____ which increase friction for gripping ability
definite patterns
–looped and whorled ridges
deepest skin layer
Reticular Dermis
Reticular Dermis contains ___ as
well as ___, ___and ____, and
deep pressure receptors called _____
-dense irregular connective tissue
-blood vessels, sweat and oil glands
-lamellar corpuscles
Found throughout the dermis (2)
-collagen
-elastic fibers
The dermis houses the (6)
-sweat glands
-hair
-hair follicles
-muscles
-sensory neurons
-blood vessels
Skin receptors (6)
- Meissner’s corpuscles
- Merkel disks
- Root hair plexus (for fine touch)
- Pacinian corpuscles
- Ruffini’s endings
- Krause’s end bulbs
Every square centimeter of your skin contains around ___ pressure receptors
14
When the body temperature is high, the capillaries of the dermis become ___. This allows body heat to radiate from the skin surface
engorged or swollen
Occur in bedridden patients who are not turned regularly
Decubitus ulcers (bed ulcers)
Hemoglobin is poorly oxygenated, both the blood and skin turn blue
Cyanosis
Effects of Emotions on Skin (4)
-Redness or erythema
-Pallor, or blanching
-Jaundice or a yellow cast
-Bruises
may indicate embarrassment (blushing), fever, hypertension, inflammation, or allergy.
Redness or erythema
Some people become pale
under certain types of emotional stress (fear, anger, and others). Pale skin may also signify anemia, low blood pressure, or impaired blood flow into the area.
Pallor, or blanching
abnormal yellow skin tone usually signifies a liver disorder in which
excess bile pigments accumulate in the blood, circulate throughout the body, and become deposited in body tissues.
Jaundice or a yellow cast
Jaundice or a yellow cast abnormal yellow skin tone usually signifies a liver disorder in which excess _____ accumulate in the blood, circulate throughout the body, and become deposited in body tissues.
bile pigments (Bilirubin)
The black-and-blue marks, where blood has escaped from the
circulation and has clotted in the tissue spaces. Such clotted blood masses are called ____
Bruises
hematomas
Skin Appendages (6)
Cutaneous Gland
Eccrine Gland
Apocrine Gland
Hair
Hair Follicles
Nails
they push into the deeper skin
regions and ultimately reside almost entirely in the
dermis.
Cutaneous Gland
Cutaneous Gland are formed by the cells of the
stratum basale
Oil glands
Sebaceous Glands
Sebaceous Glands or oil glands are found all over the skin except
-palms of the hands
-soles of the feet
Sebum is a mixture of
oily substances
fragmented cells.
is used for lubrication, and protection and prevents
hair to become brittle.
Sebum
coiled tubular structures vital for
regulating human body temperature
Sweat Glands
They produce sweat, a clear secretion that is primarily water plus some salts, vitamin C, traces
of metabolic wastes (ammonia, urea, uric acid), and lactic acid (a chemical that accumulates during
vigorous muscle activity).
Eccrine Gland
Sweat is acidic (pH from__ to ___), a characteristic
that inhibits the growth of bacteria
4 to 6
part of the body’s heat regulating
equipment
eccrine sweat glands
largely confined to the axillary (armpit) and genital areas of the body.
Apocrine glands
The apocrine glands secretion contains ___ and ____
in addition to all the substances present in eccrine
sweat; consequently, it may have a ___ or ____ color.
fatty acids, proteins
milky or yellowish
The secretion is ____, but when bacteria that live on the skin use its proteins and fats as a source of nutrients, it can take on a musky, unpleasant odor.
odorless
produced by hair follicles, are found all over the body surface
hair
Hair is found all over the body surface expect (4)
palms of the hands
soles of the feet
nipples
lips
Function of hair (3)
-serves a few minor protective functions, such as guarding the head against bumps
-shielding the eyes (via eyelashes)
-helping to keep foreign
particles out of the respiratory tract (via nose hairs).
The _____is composed of epithelial tissue and forms the hair.
inner epithelial root sheath
The ____ is actually dermal connective tissue
outer fibrous sheath
_____ provides the blood supply to the matrix in the hair bulb (the deepest part of the follicle).
Its nipple-like hair papilla
Outer fibrous sheath, this dermal region supplies _____ to the epidermal portion and reinforces it.
blood vessels
scalelike modification of the epidermis that corresponds to the hoof or claw of other animals.
nails
The borders of the nail are overlapped by folds of skin called
nail folds
The edge of the thick proximal nail fold is commonly called the
cuticle
The stratum basale of the epidermis extends beneath the nail as the
nail bed
Its thickened proximal area, called the ___, is responsible for nail growth.
nail matrix
Infections and Allergies (7)
-Athlete’s foot
-Boils (furuncles) and carbuncles
-Cold sores (fever blisters)
-Cold sores
-Contact dermatitis
-Impetigo
-Psoriasis
An itchy, red, peeling condition of
the skin between the toes, resulting from an infection with the fungus Tinea pedis.
-Athlete’s foot
_____ are caused by inflammation of hair follicles and surrounding tissues, commonly on the dorsal neck. ______ are clusters of boils often caused by
the bacterium Staphylococcus aureus.
-Boils (furuncles) and carbuncles
Small fluid-filled blisters that itch and sting, caused by human herpesvirus 1 infection. The virus localizes in a cutaneous nerve, where it remains dormant until
activated by emotional upset, fever, or UV radiation.
-Cold sores (fever blisters)
usually occur around the lips and in the mucosa of the mouth and nose
-Cold sores
Itching, redness, and swelling of the skin, progressing to blistering. It is caused by exposure of the skin to chemicals (such as those in poison ivy) that provoke allergic responses in sensitive individuals.
-Contact dermatitis
Pink, fluid-filled, raised lesions (commonly around the mouth and nose) that develop a yellow crust and eventually rupture and
weep fluid. Caused by highly contagious staphylococcus or streptococcus infections.
-Impetigo
Characterized by reddened epidermal lesions covered with dry, silvery scales that itch, burn, crack, and sometimes bleed.
Autoimmune disorder in which the immune system attacks a person’s own tissues, leading to the rapid overproduction of skin cells.
-Psoriasis
tissue damage and cell death caused by intense heat, electricity, UV radiation (sunburn), or certain chemicals (such as acids), which denature proteins and cause cell death in the affected areas.
burns
only the superficial epidermis
is damaged. The area becomes red and swollen
First-degree burns
burns involve injury to the epidermis and the superficial part of the dermis. The skin is red, painful, and blistered. Regrowth
epithelium can occur.
Second-degree burns
destroy both the epidermis and the dermis and often extend into the subcutaneous tissue, reflecting their categorization as full Second-degree burns thickness burns.
Third-degree burns
are also full-thickness burns, but they extend into deeper tissues such as bone, muscle, or tendons. These burns appear dry and leathery, and they require surgery and grafting to cover exposed tissue.
Fourth-degree burns
a surgical procedure in which a piece of skin is transplanted from one area to another
Skin graft
is the loss or removal of a body part such as a finger, toe, hand, foot, arm or leg.
Amputation
Types of Skin Cancer (4)
Basal Cell Carcinoma
Squamous Cell
Melanoma
Merket Cell
least malignant and most common skin cancer.
Basal Cell Carcinoma
relatively slow growing, and metastasis seldom occurs before the lesion is noticed.
Basal cell carcinoma
Cells of the _______, altered so that they cannot form keratin, no longer honor the boundary between epidermis and dermis.
stratum basale
Skin cancer that arises from the cells of the stratum spinosum
Squamous cell carcinoma
The lesions appear as scaly, reddened papules (small, rounded swellings) that gradually form shallow ulcers with firm, raised borders.
Squamous cell carcinoma
It grows rapidly and metastasizes to adjacent lymph nodes if not removed.
Squamous cell carcinoma
This epidermal cancer is also believed to be induced by _____
UV exposure
cancer of melanocytes
Malignant Melanoma
can begin wherever there is pigment; most such cancers appear spontaneously, but
some develop from pigmented moles.
Melanoma
It arises from accumulated DNA damage in a skin cell and usually appears as a spreading brown to black patch that metastasizes rapidly to surrounding lymph and blood vessels.
Malignant Melanoma
ABCE Rule in Malignant Melanoma Diagnosis
Asymmetry
Border Irregularity
Color
Diameter
Evolution
During the fifth and sixth months of development, a fetus is covered with a downy type of hair called ____
lanugo
By the time the infant is born, it has usually shed this hairy cloak, and instead its skin is covered with
an oily coating called the ___
vernix caseosa
This white, cheesy-looking substance, produced by the _____, protects the baby’s skin while it is floating in its water-filled sac inside the
mother.
sebaceous glands
The newborn’s skin is very thin, and blood vessels are easily seen through it. As the baby grows, its skin becomes thicker, and more ________ is deposited.
subcutaneous fat
Acne usually subsides in early adulthood, and the skin reaches its optimal appearance when we are in our ___ and ___.
twenties and thirties
As we continue to age, the amount of subcutaneous tissue decreases, leading to sensitivity to
cold
___ another result of the aging process, makes it more susceptible to bruising and
other types of injuries.
Thinning of the skin,
The decreasing ___ of the skin, along with the loss of _____, allows bags to form under our eyes, and our jowls begin to sag.
elasticity
subcutaneous fat
speed up this loss of
elasticity
smoking
sunlight
Hair loses its luster as we age, and by age ____ the number of hair follicles has dropped by ____
and continues to decline, resulting in hair thinning and some degree of baldness, or alopecia in most people.
50
one-third
Many men become bald as they age, a phenomenon called
male pattern baldness
A bald man does have hairs in the bald area. But, because those hair follicles have begun to degenerate, the vellus hairs are ___and ___
colorless
very tiny
Like balding, graying hair is usually genetically controlled by a “____” gene
delayed-action
Deep pressure receptors
Lamellar corpuscles
