Chapter 4: Integumentary System

List several important funcitions of the integumentary system and explain how these functions are accomplished.

-Keeps water and precious molecules inside the body, and other substances out. -Insulates and cushions deeper body organs. -Protects the entire body. -The uppermost layer of skin is full of keratin and is cornified, or hardened, to help prevent water loss from body's surface. The skin's rich cacpillar netwok and sweat glands regulate heat loss. -Manufactures several proteins important for immunity and synthesizes vitamin D.

sebum function

-sebum luricates the skin, keeping it soft and moist and prevents teh hair from becoming brittle -contains chemicals that kill bacteria

Name the factors that determine skin color.

1) The amount and kind of melanin in the epidermis. 2) The amount of carotene deposited in teh stratum corneum and subcutaneous tissue. The skin tends to take on a yellow-orange cast when the person eats a large amount of carotene rich foods (carrots, spinach, etc) 3) The amount of oxygen-rich hemoglobin in teh dermal blood vessels.

2 major groups of body membranes

1) epithelial memranes, including the cutaneous, mucous, and serous membranes 2) connective tissue membranes, represented by synovial membranes

burns

A burn is tissue damage and cell death caused by intense heat, electricity, UV radiatin (sunburn), or certain chemicals (such as acid), which denature proteins and cause cell death in affected areas.

ABCD rule for recognizing melanoma

Assymetry Borer irregularity Color Diameter

Why do no skin cancers develop from stratum corneum cells?

Becuse stratum corneum cells are dead.

How does the integumentary system aid in the body's heat regulation?

If you are too hot or too cold, your brain sends nerve impulses to the skin, which has three ways to either increase or decrease heat loss from the body's surface: hairs on the skin trap more warmth if they are standing up, and less if they are lying flat; glands under the skin secrete sweat onto the surface of the skin in order to increase heat loss by evaporation if the body is too hot; capillaries near the surface can open when your body needs to cool off and close when you need to conserve heat.

What are the 2 life-threatening consequences of a severe burn?

Loss of body fluids containing needed proteins and electrolytes, infection

A scalpel penetrates the left lung and enters the heart. Name the six serious membrane layers the blade passses through as it moves from the body surface into the heart.

Parietal pleura, visceral pleurra, (lung) visceral pleura, parietal pleura, parietal pericardium, visceral pericardiu, (heart)

How do the body locations of serous and mucous membranes differ?

Serous membranes line ventral body cavities closed to the exterior. Mucous membranes line body cavities open to the exterior (respiratory, digestive, urinary, and reproductive organ cavities).

Relationship between the words skin, cutaneous membrane, integument, and integumentary system.

The skin is the epithelial membrane that covers the body surface. Cutaneous membrane is a synonym for skin, as is integument, which means covering. The integumentary system is teh skin and its derivatives (nails, hair, glands).

the epidermis is _____, meaning it has no blood supply of its own

avascular

when a burn or friction causes the epidermis and dermis to separate, allowing interstitial fluid to accumulate in the cavity between layers

blister

functions of body membranes

body membranes line or cover, protect, and lubricate body surfaces

mucous membranes

composed of epithelium resting on a loos connective tissue membrane called a lamina propria line all body cavities open to exterior such as hollow organs wet membranes, often adapted for absorption or secretion

The skin appendages include ______ (4). Each of these appendages arise from the _______.

cutaneous glands, hair and hair follicles, and nails epidermis

epidermis or dermis? made up of mostly dense connective tissue, fairl tear resistant

dermis

third-degree burns

destroy the entire thickness of the skin the burned area appears blanched or blackened because the nerve endings are destroyed, the burned area is not painful regeneration is not possible

the role of nines

divides the body into 11 areas each accounting for 9 percent of total body surface

A papercut down't bleed. Has the cut penetrated into the dermis or just the epidermis?

epidermis

epidermis or dermis? made up of stratified squamos epithelium that is capable of keratizing, or becoming hard and tough

epidermis

What are the 2 types of tissue the skin is composed of?

epidermis and dermis

eccrine glands

far more numerous, found all over produce sweat, important in heat regulation

sebaceous glands, location and function

found all over the skin, excpet on palms and foot soles -produce sebum, a mixture of oily substances and fragmented cells

hair functions

guards teh head aginast bumps, shields eyes, helps keep foreign bodies out of our respiratory tract, provided warmth for early humans, not much else

second-degree burns

involve injury to the epidermis and the upper region and the dermis -skin is red and painful, and blisters appear -no permanent scars result if it is taken care to prevent infection

What componenet of the hypodermis makes it a good insulator and shock absorber?

its fatty tissue

What cell type is most abundant in the epidermis?

keratin

most of the cells in the epidermis are _______, which produce keratin, the fibrous protein that makes the epidermis a tough, protective layer

keratinocytes

apocrine glands

largely confined to the axillary (armpit) and genital areas of the body -larger than eccrine glands; their ducts empty into hair follicles -secretions contain fatty acids and proteins in addition to the ingredients of eccrine secretions

serous membrane

line body cavities closed to exterior often occur in pairs, the parietal layer lines a specific portion of the wall of the ventral body cavity and it folds in on itself to form the visceral layr, which covers teh outisde of the organs in that cavity

Where would you find a synovial membrane?

lining a fibrous capsule surronding a joint

What change in aging skin accounts for wrinkles and cold intolerance for older adults?

loss of subcutaneous fat

What does skin protect the entire body from?

mechanical damage (cut and bumps), chemical damage, thermal damage, UV radiation, desiccation (drying out), and bacteria.

What pigments determine skin color?

melanin, carotene, oxygen-rich hemoglobin

hairs

not found on palms, soles, nipples, and lips humans are born with as many hair follicles as they will ever have

first degree burns

only the epidermis is damaged; the area becomes red and swollen -not usually serious; generally heal in 2-3 days

The dense connective tissue making up the tissue of teh dermis consist of 2 major regions, the upper dermal region, the _____ and the deepest skin layer, the _______.

papillary and teh recticular areas

Which layer of the epidermis prouces new epidermal cells?

stratum basale

Excess shedding of scales from the superficial layer of the skin of the scalp causes dandruff. What is the name of this skin layer?

stratum corneum

anchors the skins to underlying organs and provides a site for nutrient (fat) storage

subcutaneous tissue, or hypodermis

What is the single most common risk factor for skin cancer?

sun exposure

sweat glands, location, types and function

widely distributed in the skin -eccrine and apocrine

cutaneous membrane

your skin! superficial epidermis and then an underlying epidermis of fibrous connective tissue exposed to air, dry embrane