Ch.5 Integumentary System

the fibrous protein that is responsible for the strength and water resistance of the skin surface is

keratin pg 148

skin receptors for light touch are found in the stratum basale from the epidermis but are also located in the dermis within the ______?

papillary

the layer of skin that contains the blood vessels and nerves that are closest to the surface of the skin is?

papillary

what are the 2 major components of the dermis?

papillary layer and reticular layer pg152

muscle weakness and reduction in the bone strength in the elderly result from decreased___?

vitamin D3 production pg150-152

what 2 pigments produce the skin color?

carotene: orange pigment melanin: yellow-brown pigment

Earwax is produced by_____ glands

ceruminous

A surgical i8ncision parallel to the lines of the cleavage

closes and heals with relatively little scarring

the stratum corneum of the nail root, which extends over the exposed nail, is called the___?

eponychium pg160

What are the skin cells and their function?

found in the EPIDERMIS: • Keratinocytes --- are most epidermis cells, which produce fibrous proteins. • Melanocytes --- are spider-like black cells that produce the brown-to-black pigment called melanin. The melanocytes are located in the stratum germinativum. • Langerhans' cells --- activate immune system response in the stratum spinosum. • Merkel cells --- are in the conjunction with sensory nerve ending in the stratum germinativum. found in the DERMIS: Fibroblasts-in connective tissue proper, they produce protein and collagen fibers macrophages-engulf damaged cells or pathogens that enter tissue adipocytes-fat cells, droplets

what are the skin receptors and their functions?

found in the dermis: -Free nerve endings that detect pain and temperature Meissner (tactile) corpuscles: mechanoreceptors that sense light touch found in the papillary layer Lamellated corpuscles receptors for deep pressure and vibration found in the reticular layer

the accessory structures of the integument include the ?

hair follicles, nails, sebaceous glands, and sweat glands

what factors affect skin color?

high/low oxygen levels illness: jaundice (yellow) addisons (bronze) and tumors affecting pituitary gland. and vitiligo: loose melanocytes(nuerological disorders)

what widespread effects does epidermal growth factor(EGF) have on the integument?

-promoting the divisions 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 pg152

list the four stages in the regeneration of the skin after and injury

1. bleeding/inflammatory phase 2. scab formation/migratory phase 3. granulation tisse formation/proliferation phase 4.scarring/maturation phase pg162

what two major layers constitute the dermis, and what components are in each layer?

1.Papillary layer-consist of loose connective tissue and contains capillaries and sensory neurons 2Reticular layer- consists of dense irregular connective tissue and bundles of collagen fibers Both layers contain networks of blood vessels, lymphatic vessels, and nerve fibers pg152

while walking barefoot on the beach, Joe stepped on a thorn that penetrated on the sole of his foot to the dermis. How many layers of epidermis did the thorn penetrate?

5 layers

apocrine sweat glands in the skin are located in the following body regions?

Axillary, mammary and genital (armpits)

What are the 2 major components of the Integumentary system?

Cutaneous membrane and accessory structures

How vitamin D is produced, what is its function?

Epidermal cells produce cholecalciferol (vitamin D3) In the presence of UV radiation function is to maintain normal bone development. if not produced, abnormal bone development occurs ( e.g.rickets)

what are the functions of the integumentary system?

Protection of underlying tissues and organs Glands in skin excretes salts, water, and urea Maintenance of body temperature (insulation and evaporation) Production of melanin Production of keratin Synthesis of vitamin D3 Storage of lipids Detection of touch, pressure, pain, and temperature

what are the cells in the hypodermis

adipocytes fibroblasts macrophages

in which layers of the epidermis does cell division occur?

at the stratum basale pg 147 *because basal cells dominate the stratum basale with stem cells

beginning at the basement membrane and traveling toward the free surface, the epidermis includes which following layers?

basale, spinosum, granulosum, lucidum, corneum.

the cutaneous plexus and papillary plexus consists of

blood vessels providing the dermal blood supply pg153/154

exposure of the skin to ultraviolet radiation_______?

can result in damage to the DNA of cells in the stratum basale pg150

what are the cleavage lines and what is their importance

pattern of fiber bundles in skin Importance: cut parallel to cleavage line will heal with little scarring whereas cut against it will pull open and result in greater scarring (e.g. surgeons/surgery performing incisions.)

in order for bacteria on the skin to cause an infection in the skin, they must accomplish all of the following except___?

penetrate to the level of the capillaries

the portion of the hair follicle where cell divisions occur is the ___?

pg.157 hair matrix

the primary function of sensible perspiration is to___?

reduce body temp pg148 *know its happenening(ex. excersising and you can feel the sweat)

skin receptors for deep pressure and vibration are located in the ______ of the dermis

reticular

the layer of the skin that contains bundles collagen and elastic fibers responsible for the strength of the skin is the ____ layer?

reticular

what are the 2 types of exocrine glands in the skin?

sebaceous and sweat glands pg158

What is the body location of sweat glands and sebaceous glands?

sebaceous glands are found everywhere in the body except hands and soles sweeat glands: 2 types apocrine glands-Found in axillary and genital areas produce a fluid that is rich in proteins and fats. Found in armpits, around nipples, and groin Merocrine (eccrine) glands-Found in the rest of the body produce a clear watery secretion.Widely distributed on body surface Especially on palms and soles to "cool" skin

what type of epithelium is the skin?

stratified squamous

The layer of stem cells that constantly divide to renew the epidermis is?

stratum basale

What epidermal layers are found in THIN skin?

stratum basale stratum spinosum stratum granulosum stratum corneum

What epidermal layers are found in THICK skin?

stratum basale stratum spinosum stratum granulosum stratum lucidum stratum corneum

Each of the following is a function of the integumentary system except?

synthesis of vitamin c pg. 145-146

apocrine sweat glands can be controlled by?

the autonomic nervous system(ANS) and endocrine system pg160

the darker and individuals skin color:

the more melanin her melanocytes produce pg149

what is the function of arrector pili muscles?

these smooth muscles cause hair to stand erect when stimulated

The type of burn that may require a skin graft is a?

third-degree burn

what are the characteristics of the epidermal layers?

• Stratum corneum --- is the outermost layer and consists of 15-30 stratified squamous cells. Shingle-like dead cells. • Stratum lucidium --- is a very thin band of the flattened dead cells. Occurs only in thick skin • Stratum granulosum --- is a thin layer and contains lipids and granules. • Stratum spinosum --- activates immune system. • Stratum germinativum --- is a single row of cells. The cells are constantly undergoing cell division (mitosis) to produce new cells. It takes 15-30 days for a cell to move from the stratum germinativum to the stratum corneum. The layer also contains pigment cells called melanocytes.

What is the classification of skin burns and what are their consequences?

• Tissue damage and cell death caused by heat, electricity, UV radiation, or chemicals. • Associated dangers: Dehydration, Electrolyte imbalance, Circulatory shock Severity of Burns • First-degree burns: - Only epidermis is damaged - Skin is red and swollen • Second degree burns: - Epidermis and upper dermis are damaged - Skin is red with blisters • Third-degree burns - Destroys entire skin layer. Burn is gray-white or black - Burns are considered critical if: o Over 25% of body has second degree burns o Over 10% of the body has third degree burns o There are third degree burns of the face, hands, or feet