© 2009 Delmar, Cengage Learning Chapter 5 Integumentary System

© 2009 Delmar, Cengage Learning

Chapter 5

Integumentary System


Integumentary System

• Skin and its appendages– Hair

– Nails

– Sebaceous glands

– Sweat glands

• Integumentary means covering

• 3,000 square inches of surface area


Animation – Skin

Click Here to play Skin animation


Functions of Skin

• Covering

• Regulate body temperature

• Manufacture Vitamin D

• Nerve receptors


Functions of Skin

• Temporary storage

• Screen out ultraviolet radiation

• Special absorptive properties


Structure of the Skin

• Epidermis – Outermost covering

– Avascular

• Dermis– True skin

– Connective tissue

– Vascular


Structure of the Skin


Epidermal Cells

• Keratinocytes

• Merkel cells

• Melanocytes

• Langerhans cells


Epidermal Layers

• Stratum germinativum

• Stratum spinosum

• Stratum granulosum

• Stratum lucidum

• Stratum corneum


Dermis

• Also called corium

• Thicker, inner layer of the skin

• Many nerve receptors

• Blood vessels and heat regulation


Subcutaneous Layer

• Also called hypodermal layer

• Lies under dermis

• Not a true part of the integumentary system

• Attaches integumentary system to the surface muscles underneath


Appendages Hair

• Root shaft

• Outer cuticle layer

• Cortex

• Inner medulla

• Hair follicle

• Arrector pili muscle


Appendages Nails

• Hard structures covering the dorsal surfaces

of the last phalanges of the fingers and toes

• Nail bed or matrix

• Diseases and nail color


Appendages Sweat Glands

• Also called sudoriferous glands

• Perspiration 99% water

• Perspiration is excreted through pores

• Under the control of the nervous system

• 500ml water lost per day through skin

• Ceruminous or wax glands


Sebaceous Glands

• Secrete sebum which is thick, oily substance

• Sebum lubricates the skin, keeping it soft and pliable


Microorganisms

• Intact skin is the best way to protect itself against pathogens

• Most skin bacteria are associated with hair follicles and sweat glands

• Handwashing– Most effective action to prevent spread of disease

• 20 seconds for washing hands

• 2-4 minutes for infectious material


Aging

• Becomes more fragile and dry

• Loss of elasticity

• Less effective body temperature control

• Melanocytes decrease

• Physiological changes can impact self-worth


Disorders Skin

• Acne vulgaris– Common and chronic disorder of sebaceous glands

• Athlete’s foot– Contagious fungal infection

• Dermatitis– Inflammation of the skin


Disorders Skin

• Eczema– Acute or chronic, noncontagious inflammatory skin disease

• Impetigo– Acute, inflammatory, and contagious skin disease

• Psoriasis– Chronic inflammatory skin disease (reddish patches covered

by silvery-white scales)


Disorders Skin

• Ringworm– Highly contagious fungal infection

• Urticaria (hives)– Intensely itching wheals or welts

• Boils (carbuncles)– Painful, bacterial infection

of the hair follicles or sebaceous glands


Disorders Skin

• Rosacea– Common inflammatory disorder (chronic redness and irritation

to the face)

• Herpes– Viral infection which is usually seen as a blister


Disorders Skin

• Genital herpes– Virus which may appear as a blister in the genital area

• Shingle (herpes zoster)– Skin eruption due to a virus infection of the nerve ending


Disorders Hair and Nails

• Head lice– Parasitic insects

• Ingrown nails– Common nail problem


Disorders Hair and Nails

• Fungal infections– Infections of the nail

• Warts– Viral infections that affect the skin surrounding or underneath

the nail


Skin Cancer

• Basal cell carcinoma

• Squamous cell carcinoma

• Malignant melanoma

• Skin and sun exposure


Burns

• Rule of nines

• First degree burns

• Second degree burns

• Third degree burns


Skin Lesions

• Pressure ulcer (decubitus ulcers)– Stage I

– Stage II

– Stage III

– Stage IV

Documents

© 2009 Delmar, Cengage Learning Chapter 5 Integumentary System