Chapter 5
THE INTEGUMENTARY SYSTEM
Chapter Synopsis
Students are introduced to the structure and function of the skin and its epidermal derivatives, including hair, skin, glands, and nails. Factors contributing to skin color and skin superficial and deep wound healing are also discussed. A comparison of the structural and functional differences in thin and thick skin is discussed. The effects of aging on the integumentary system and developmental anatomy of the system are also included. Clinical applications that are described include skin grafts, psoriasis, skin color as a diagnostic clue, acne, impacted cerumen, hair removal, transdermal drug administration, and photodamage. Disorders of the skin that are discussed include skin cancer, burns, and pressure sores. This chapter has the first of ten focus boxes which explains how the integumentary system contributes to the homeostasis of the entire body. The chapter concludes with a glossary of medical terminology associated with the integumentary system.
Chapter Outline and Objectives
INTRODUCTION
- Briefly list the functions of the integumentary system.
STRUCTURE OF THE SKIN
- Describe the two principal parts of the skin.
- Discuss the structure and function of the subcutaneous layer.
Epidermis
- Name the four principal types of cells found in the epidermis and their roles.
- List the layers of the epidermis.
Stratum Basale
- Describe the features of the stratum basale.
- Discuss the use of skin grafts in epidermal injury.
Stratum Spinosum
- Describe the features of the stratum spinosum.
Stratum Granulosum
- Describe the features of the stratum granulosum.
Stratum Lucidum
- Describe the features of the stratum lucidum.
Stratum Corneum
- Describe the features of the stratum corneum.
Keratinization and Growth of the Epidermis
- Describe the process of keratinization and the role of hormones in the process.
- Discuss the events of psoriasis and list the various treatments for this problem.
Dermis
- Discuss the two layers of the dermis in terms of the connective tissue cells and matrix, as well as the host of sensory receptors, immune cells, adipocytes, and functional extensions of the epidermis.
- Discuss the appearance, development, and uniqueness of the epidermal ridges.
- Discuss the effects of exposure to the sun on the skin.
The Structural Basis of Skin Color
- Explain the basis for skin color function and variation.
- Discuss the use of skin color as a diagnostic clue for certain conditions.
ACCESSORY STRUCTURES OF THE SKIN
- Explain what is meant by epidermal derivative, and the organs that are in this category.
Hair
- Discuss the location of hair in the adult.
Anatomy of a Hair
- Describe the cell types involved in production of the hair root and follicle, and how they are related to the structures of the sheath layers.
- List the accessory structures (nerves, erector pilli muscle, sebaceous gland, etc.) and their functional relation to the hair follicle.
- Compare and contrant the function of a depilatory and electrolysis in hair removal.
Hair Growth
- Discus the growth and resting stages of the hair cycle.
- Explain how chemotherapeutic agents cause hair loss.
Hair Color
- Discuss the role of melanin in hair color.
Functions of Hair
- List and describe the functions of hair.
- Discuss the role of hormones in the growth and loss of hair.
Skin Glands
- List the different types of skin glands.
Sebaceous Glands
- Explain the distribution and size of glands over the body, as well as the content, function, and dysfunction of the sebum secretion.
- Describe the cause, location, and possible outcome of acne.
Sudoriferous Glands
- Discuss the different structures, locations, and secretions of the two types of sudoriferous glands.
Ceruminous Glands
- Discuss the specialized location of ceruminous glands and the difference in purpose between cerumin and sebum.
- Discuss the effect of impacted cerumen on hearing and the treatment for the condition.
Nails
- Describe the components of the fingernails and toenails and their growth pattern.
- Examine pathologic nail conditions and the conditions they may indicate.
TYPES OF SKIN
- Compare the structural and functional differences between thick and thin skin
FUNCTIONS OF SKIN
- List the functions of skin.
Thermoregulation
- Explain the role of the skin in helping to maintain the homeostasis of normal body temperature.
Protection
- Describe the role of the skin in providing a physical, chemical, and biological barrier for protection.
Cutaneous Sensations
- Briefly discuss the types of cutaneous sensations that are associated with the skin.
Excretion and Absorption
- Discuss the role of the skin in excretion of substances from the body and in absorption.
Synthesis of Vitamin D
- Discuss the role of the skin in vitamin D synthesis.
- Discuss the process of transdermal drug administration.
MAINTAINING HOMEOSTASIS: SKIN WOUND HEALING
- List the two kinds of skin wound healing, based on the depth of the injury.
Epidermal Wound Healing
- Outline the causes, description, and steps involved in epidermal wound healing.
Deep Wound Healing
- Outline the causes, description, and steps involved in deep wound healing.
DEVELOPMENT OF THE INTEGUMENTARY SYSTEM
- Describe the development of the epidermis, its derivatives, and the dermis.
AGING AND THE INTEGUMENTARY SYSTEM
- Describe the causes and effects for the following skin disorders: burns, sunburn, skin cancer, acne, and pressure sores.
- Discuss the effect of overexposure to the sun on the skin.
DISORDERS; HOMEOSTATIC IMBALANCES
Skin Cancer
- Discuss the types of skin cancer and the risk factors for skin cancer.
Burns
- Distinguish between the characteristics of first, second, and third degree burns, and their treatment.
Pressure Sores
- Discuss the cause of pressure sores.
FOCUS ON HOMEOSTASIS; THE INTEGUMENTARY SYSTEM
- Examine the role of the integumentary system in maintaining homeostasis throughout the body.
MEDICAL TERMINOLOGY
- Define medical terminology associated with the integumentary system.
