Transcript Skin cancers and melanomas CLE 3251.2.2

The Integumentary System
Chapter 5
Standards and Objectives
CLE 3251.2.1 Identify structures of the
integumentary system and show the relationship
between these structures and their functions.
 Identify the structures of the skin and explain
their role in protecting the body and maintaining
homeostasis.
CLE 3251.2.2 Investigate physiological
mechanisms that allow the integumentary system
to function.
 Explain the physiological processes involved in
healing the skin and disorders of the skin.
 Construct a labeled model of the skin with
descriptions of its functions.
Facts about the Integumentary
System
Your skin is considered the largest organ in the human body.
2. Your skin is made up of three major layers - epidermis,
dermis, and hypodermis (also called the subcutaneous
tissue).
3. Your skin protects your inside organs while keeping
infections out and prevents you from getting sick.
4. Your skin loses about 30,000 to 40,000 dead skin cells from
the surface almost every minute and about 60-100 strands
of hair per day, even though you do not see it happening.
5. Your skin sheds a layer of these dead cells every 24 hours
and renews itself about every 28 days.
6. Your skin swells when it absorbs water.
7. Your skin contains a protein called keratin which is also
found in hair and nails
8. Your skin is the thinnest on the eyelid.
9. Goose bumps are actually little pimples that help retain a
layer of warm air over our body.
10.About 32 million bacteria call every inch of your skin home.
1.
CLE 3251.2.1 Identify structures of the
integumentary system and show the
relationship between these structures and
their functions.
 Identify the structures of the skin and
explain their role in protecting the body
and maintaining homeostasis.
Skin Structure



Epidermis: (epi – above) superficial epithelium
Dermis: underlying area of connective tissues
Hypodermis: AKA subcutaneous layer –loose
connective tissue that separates the dermis
from the deep fascia around other organs such
as muscles or bones
◦ Fascia: connective tissue fibers, primarily
collagenous, that form sheets or bands beneath the
skin to attach, stabilize, enclose, and separate
muscles and other internal organs
◦ Collagenous: made of strong, insoluble protein
fibers that are common in connective tissues
Skin Functions
Protection
Excretion of wastes
Temperature regulation
Synthesis of compounds
◦ Melanin
◦ Keratin
◦ Calcitrol
 Storage of chemical compounds
◦ Lipids
 Sensations




The Skin
Figure 5-1
Components of the Integumentary System
https://www.youtube.com/watch?v=
yKAzVC0WcmI
Changes in skin appearance can help
diagnose diseases





Jaundice: the liver is unable to excrete bile, so a yellowish
pigment accumulates in body fluids, and in advanced stages,
the skin and whites of the eyes turn yellow
Some tumors affecting the pituitary gland result in
secretion of large amounts of melanocyte-stimulating
hormone (MSH), causing a darkening of the skin, as it the
individual has an extremely dark bronze tan.
Addison disease: the pituitary gland secretes large
quantities of adrenocorticotropic hormone (ACTH), which
is similar to MSH
Vitiligo: Melanocytes are lost due to immune defense
malfunctions, where antibodies attack normal melanocytes,
causing light spots on primarily dark-skinned individuals
Skin cancers and melanomas
CLE 3251.2.2 Investigate physiological
mechanisms that allow the integumentary
system to function.
 Explain the physiological processes
involved in healing the skin and disorders
of the skin.
 Construct a labeled model of the skin
with descriptions of its functions.
Skin Cancer

Basal Cell Carcinoma
◦ Most common, least malignant skin cancer
◦ Usually occurs on face
◦ Rx – surgical removal or radiation

Squamous Cell Carcinoma
◦ Mostly scalp and lower lip
◦ Grows rapidly and metastasizes to lymph nodes
◦ Rx – surgical removal or radiation
◦ Prognosis good with early diagnosis
Skin Cancer

Melanoma
◦ Occurs in melanocytes
◦ Metastasizes to other areas quickly
◦ Appears as brown or black irregular patch that occurs
◦ Suddenly
◦ A change in an existing wart or mole may indicate
◦ Melanoma
◦ Rx – surgical removal of melanoma and surrounding area
◦ and chemotherapy
Basal Cell Carcinoma
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Squamous Cell Carcinoma
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Melanoma
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Dermal Blood Supply and Innervation



Cutaneous plexus: supplies the skin, hair follicles,
sweat glands, and other structures in the dermis with
blood, nutrients, and oxygen
Papillary plexus: provides blood to capillary loops
that follow the contours of the epidermis-dermis
boundary
◦ Trauma to the skin often results in a contusion
(bruise),
Innervation : Nerve fibers in the skin control blood
flow, adjust gland secretion rates, and monitor sensory
receptors in the dermis and deeper layers of the
epidermis
Dermal Circulation
Section 5.6: Hypodermis



AKA Subcutaneous Layer
Consists of areolar and adipose tissues and is quite elastic
Is a fatty layer that:
◦ provides extra insulation
◦ helps reduce heat loss
◦ serves as an energy
reserve and a shock
absorber for rough
activities.
Section 5.10 – Regeneration of Skin
Bleeding occurs when damage extends through the
epidermis into the dermis.
 Blood clot (scab) forms at the surface, temporarily
restoring the integrity of the epidermis and restricting
entry of additional microorganisms into the damaged
area.
 Over time, deeper portions of the clot dissolve, and the
number of capillaries decline. Fibroblast activity leads to
the appearance of collagen fibers and typical ground
substance.
 Formation of an inflexible, fibrous, noncellular scar
tissue completes the repair process, but does not
restore the tissue to its original condition.

Disorders of the Skin

ACNE VULGARIS
◦ Common and chronic disorder of sebaceous
glands
◦ Sebum plugs pores; area fills with leukocytes
◦ Also – blackheads, cysts, pimples and scarring
Disorders of the Skin

ACNE VULGARIS
Disorders of the Skin

ATHLETE’S FOOT
◦ Contagious fungal infection
◦ Usually contracted in public baths and showers
◦ Rx – antifungal agents
Disorders of the Skin

DERMATITIS
◦ Non-specific inflammation of skin
◦ Can be rash – reaction to soap, plants, etc.
◦ Can be emotional – stress can cause skin
blotches
Disorders of the Skin

ECZEMA
◦ Acute or chronic, inflammatory skin disease
◦ Dry, red, itchy and scaly
◦ Rx – remove or avoid causative agent,
hydrocortisone to help alleviate the symptoms
Disorders of the Skin

WARTS (VERRUCAE)
◦ Caused by virus
◦ Some disappear spontaneously, others
removed with
liquid nitrogen, chemicals or laser
Disorders of the Skin

IMPETIGO
◦
◦
◦
◦
Acute, inflammatory and contagious
Seen in babies and young children
Caused by staphylococcus or streptococcus
Characterized by the appearance of vesicles which
rupture and develop distinct yellow crusts
Disorders of the Skin

PSORIASIS
◦ Chronic inflammatory skin disease characterized by dry
reddish patches which are covered with silvery-white
scales
◦ Affects the skin surface over elbows, knees, shins, scalp
and lower back
◦ Cause – unknown
◦ Onsets triggered by stress,
trauma or infection
Disorders of the Skin

RINGWORM
◦
◦
◦
◦
◦
Highly contagious fungal infection
Can be contracted from infected animals
Raised, itchy circular patches with crusts
Skin, scalp or underneath nails
Rx – griseofulvin (drug)
Disorders of the Skin

BOILS (CARBUNCLES)
◦ Painful, bacterial infection of hair follicle or
sebaceous glands
◦ Caused by staphylococcus organism
◦ Rx – antibiotics, excision and drainage of
affected area
Disorders of the Skin

SHINGLES (HERPES ZOSTER)
◦ Viral infection of nerve endings
◦ Can be caused by dormant chicken pox virus
◦ Chest or abdomen, accompanied by severe
pain
◦ Rx – medication for pain and itching
Disorders of the Skin

HERPES SIMPLEX I
◦ Viral and contagious
 Spread by kissing, eating/drinking after infected
person, sharing lipstick, etc.
◦ Symptom includes Fever blister or cold sore
Disorders of the Skin

SCABIES
◦ Communicable, severe itching
◦ Contracted from infected living or nonliving
things
◦ Mite burrows in skin, lays eggs, eggs hatch
Burns
• A simple, moderately severe sunburn damages
the blood vessels extensively. How extensively?
Studies have shown that it can take four to fifteen
months for them to return to their normal condition.
Consider that the next time you’re feeling too lazy to
apply sunscreen before heading outside.
 Caused by radiation, sun, boiling water,
chemicals, fire or electricity


RULE OF NINES – Measures percent of body
burned.
Body divided into 11 areas; each is 9% of body
surface.

FIRST DEGREE BURNS
◦
◦
◦
◦
◦
Superficial
Skin red and dry
Involves only epidermis
Rx – cold water
Healing within one week

SECOND DEGREE BURNS
◦
◦
◦
◦
◦
Epidermis and dermis
Pain, swelling, redness and blistering
Skin may be exposed to infection
Rx – pain medication, dry sterile dressing
Healing within 2 weeks

THIRD DEGREE BURNS
◦ Epidermis, dermis and subcutaneous layers
◦ Symptoms – loss of skin, blackened skin
◦ May be life threatening