Anatomy and Physiology: Chapter 5

What are the two major components of the integumentary system?

Cutaneous membrane

Accessory structures

What are the two components of the cutaneous membrane?

Epidermis

Dermis

Hypodermis

Loose connective tissue deep to the dermis that separates the integument from the deep fascia around other organs

What are the general functions of the skin and hypodermis? (7)

Protection of underlying tissues and organs

Excretion of salts, water, and organic wastes

Maintenance of body temperature

Production of keratin

Synthesis of vitamin D

Storage of lipids

Detection of touch, pressure, pain, and temperature stimuli

What layer is in thick skin and not in thin skin?

Stratum Lucidum

Where do you find thick skin?

Palms of the hands and soles of the feet

What are the layers of the skin from most deep to most superficial?

Stratum basale

Stratum spinosum

Stratum granulosum

Stratum lucidum

Stratum corneum

What are thet wo factors in the color of the epidermis?

Dermal blood supply

Epidermal pigmentation

Insensible perspiration

Water loss that you are unable to feel or see

Sensible perspiration

Water loss that you are aware of

Carotene

Orange-yellow pigment that noramlly accumalates in epidermal cells

Keratin

Tough, fibrous protein that is the basic component of hair and nails

Keratinization

The formation of protective, superficial layers of cells filled with keratin

Melanin

A brown, yellow-brown, or black pigment produced by melanocytes

Where will you find melanocytes?

Stratum basale

What protects your skin from significant amounts of ultraviolet radiation?

Melanin

What is the name of the pigment in red blood cells?

Hemoglobin

Cyanosis

When skin takes on a blue coloration

How is vitamin D3 made in the body?

When epidermal cells in the stratum spinosum and stratum basale are exposed to ultraviolet radiation and convert a cholesterol related steroid ito the vitamin

What vitamin is needed in order to synthesize the hormone calcitrol?

Vitamin D3

What is the ABCDE of skin cancer characteristics?

A - Asymmetry

B - Border

C - Color

D - Diameter

E - Evolution

What are some of the roles of EGF? (4)

Promoting the division of basal cells in the stratum basale and stratum spinosum

Accelerating the production of keratin in differentiating keratinocytes

Stimulating epidermal development and epidermal repair after injury

Stimulating synthetic activity and secretion by epithelial glands

What are the two major components in the dermis?

Papillary layer

Reticular layer

Dermatitis

An inflammation of the skin that primarily involves the papillary layer

What happens when you cut parallel to a cleavage line?

It will usually remain closed and heal with little scarring

What do nerve fibers in the skin do? (3)

Control blood flow

Adjust gland secretion rates

Monitor sensory receptors in the dermis and the deepest layers of the epidermis

Tactile discs

Sensory terminals that monitor the tactile cells located in the deepest layers of the epidermis

Tactile corpuscles

Receptors that are sensitive to light touch that are located in the dermal papillae

Lamellated corpuscles

Receptors that are sensitive to deep pressure and vibration that are located in the reticular layer

What is one reason why the hypodermis is important?

It is important in stabilizing the position of the skin in relation to underlying tissues while permitting independent movement

What are the functions of subcutaneous fat?

Provides extra insulation

Reduce heat loss

Energy reserve

Shock absorber

What surrounds the base of each hair follicle?

A plexus of sensory nerves

What happens when the arrector pili contracts?

It causes "goose bumps"

Club hair

When a follicle becomes inactive at the end of the hair growth cycle

Vellus hairs

Fine "peach fuzz" hairs located all over the body

Terminal hairs

Heavy, more deeply pigmented, and sometimes curly

Why do people get white hairs? (2)

Lack of pigment

Presence of air bubbles in medulla of the hair shaft

Sebaceous glands

(Oil glands) Holocrine glands that discharge an oily lipid secretion into hair follicles

What are some functions of sebum? (3)

Inhibits the growth of bacteria

Lubricates and protects keratin of hair shaft

Conditions surrounding skin

Sebaceous follicles

Large sebaceous glands that are not associated with hair follicles; their ducts discharge sebum onto the epidermis

Seborrheic dermatitis

An inflammation around abnormally active sebaceous glands

What are the two types of sudoriferous glands?

Apocrine sweat glands

Merocrine sweat glands

Apocrine glands (Locations and discharge locations)

Located in the armpits, around the nipples, and in the pubic region

Secrete their products into hair follicles

Merocrine glands/eccrine (Discharge locations)

Secrete their products directly onto the surface of skin

What are the functions of merocrine sweat gland activity? (3)

Cooling the surface of the skin to reduce body temperature

Excreting water and electrolytes

Providing protection from environmental hazards

Ceruminous glands

Modified sweat glands in the passageway of the external ear

What controls the activation and deactivation of sebaceous and apocrine glands at the subconscious level?

Autonomic Nervous System (ANS)

Where does nail production occur?

Nail root

What does the body of the nail consist of?

Dead, tightly compressed cells packed with keratin

Granulation tissue

The combination of blood clot, fibroblasts, and an extensive capillary network

Keloid

Thick, raised area of scar tissue

What are the four steps for the repair of injury to the integument?

Inflammatory phase

Migratory phase

Proliferation phase

Maturation phase