Cutaneous (skin)

Accessory

Originate in the Dermis

-hair

-nails

-multicellular exocrine glands

1. Protects

2. Excretes

3. Maintains

4. Synthesizes

5. Stores

6. Detects

-Avascular stratified squamous epithelium

-Nutrients and Oxygen diffuse from capillaries in the dermis

-contain large amounts of keratin

-the most abundant cells in the epidermis

-covers the paolms of the hands and soles of the feet

-Has 5 layers of keratinocytes

-covers most of the body

-has 4 layers of keratinocytes

Stratum Germinativum (germinativum layer)

-has many germinative stem cells or basal cells

-is attached to basal lamina by hemidesmosomes

-forms a strong bond between epidermis and dermis

-Epidermal Ridges (Finger Prints)

-Dermal Papillae (tiny mounds)

-increase the area of basal lamina

-strengthen attachment between epidermis and dermis

-Merkel Cells

-Melanocytes

-found in hairless skin

-respond to touch (trigger nervous system)

-contain pigment melanin

-scattered throughout stratum germinativum

-produced by division of stratum germinosum

-8-10 layers of keratinocytes bound by desmosomes

-cells shrink until cytoskeletons stick out (spiny)

-Continue to divide, increasing thickness of epithelium

-contain Langerhans Cells, active in immune system

a tough, fibrous protein

-makes up hair and nails

-dense granules

-cross-link keratin fibers

-Produce protein fibers

-dehydrate and die

-create tightly interlocked layers of keratin surrounded by keratohyalin

-Found only in thick skin

-covers Stratum Granulosum

-flat

-dense

-filled with keratin

-exposed surface of skin

-15-30 layers of keratinized cells

-water resistant

-shed and reproduced every two weeks

-the formation of a layer of dead, protective cells filled with keratin

-occurs on all exposed skin surfaces except eyes

WATER LOSS THROUGH SKIN

-from damage to stratum corneum (burns and blisters)

-from immersion in hypertonic solution (Seawater)

water gain through skin

-results from immersion in hypotonic colution (freshwater)

-causes stretching and wrinkly skin

-yellow, brown or black pigment

-produce by melanocytes

-stored in transport vehicles (melanosomes)

-transferred to keratinocytes

-orange-yellow pigment

-found in orange vegetables

-accumulates in epidermal cells and fatty tissues of the dermis

-can be converted to Vitamin A

-Melanin protects skin from sun damage

-skin color depends on melanin production, not number of melanocytes

-Ultraviolet Radiation

-blood vessels dilate from heat, skin redness

-blood flow decreases, skin pales

-bluish skin tint

-caused by severed reductino in blood flow or oxygenation

buildup of bile produced by liver

-yellow color

-disease of pituitary gland

- skin darkening

-loss of melanocytes

-loss of color

Nevus (Mole)

Freckles

Hermangioma

most common birthmark

-become visible within the first two weeks of life, continue to grow til 6-9 months. Then, gradually lose red color.

E.G. Strawberry Hermangioma

"Port Wine Stain" or "Nevus Fammeus"

-flat, pink, red, or purple mark that appears at birth, face, arm or leg, continues to grow as child grows

-fingers, toes, palms, soles

-Helps grasp objects

-increase friction

-leave noticable prints

-ease has individual pattern

-valuable tool in law enforcement and identification

Cholecalciferol (Vitamin D3)

-the presence of UV radiation

-powerful peptide growth factor

-produced by glands (salivary and duodenum)

-used in laboratories to grow skin grafts

-promote division of germinative cells

-accelerates keratin production

-stimulates epidermal repair

-stimulates glandular secretion

-located between the epidermis and subcutaneous layer

-anchors epidermal accessory structures (hair follicles and sweat glands)

outer papillary layer

deep reticular layer

-Consists of dense irregular connective tissue

-contains larger blood vessels, lympth vessels and nerve fibers

-contains collagen and elastic fibers

-contains connective tissue proper

-consists of aerolar tissue

-contains smallaer capillaries, lymphatics and sensory neurons

-has dermal papillae projecting between epidermal ridges

-An inflammation of the papilary layer

-caused by infection, radiation, mechanical irritation, or chemicals

-characterized by itch or pain

-strong, due to collagen fibers

-elsastic due to elastic fibers

-flexible (skin turgor)

-dehydration

-age

-hormonal changes

-UV exposure

-Thickened Tissue resulting from:

-excessive stretching of skin from pregnancy or weigh gain

establish important patterns

-a parallel cut remains shut, heals well

-a cut across pulls open scars

-lies below the integument layer or hypodermis

-stabilizes the skin

-allows seperate movement

-made of elastic areolar and adipose tissues

-connected to the reticular layer or integument by connective tissue fibers

-has few capilaries and no vital organs

is the site of subcutaneous injections using hypodermic needles

distribution patters determine by hormones

-can be reduced by liposuction

-located deep in the dermis

-produces nonliving hairs

-is wrapped in a dense connective-tissue sheath

-involuntary smooth muscle

-causes hairs to stand up

-produces "goose bumps"

-lubricate the hair

-control bacteria

Hair Root

-LOWER part of the hair

-attached to INGRUMENT

-UPPER part of the hair

-NOT ATTACHED to the integument

-a layer of dividing basal cells

-produce hair structure

-push hair up and out of skin

is not growing

-attached to innactive follicle

-inner layer

-contacts the cuticle in lower hair root

-a dense connective-tissue sheath

-contacts connective tissues of dermis

-Heavily pigmented

-on head, eyebrows, and genitalia after puberty

-production of melanocytes at the hair papilla moved into the hair matrix

-determined by genes

Contain:

-simple branched alveolar glands

-sebaceous follicles

-holocrine glands

-secrete sebum

-contains lipids and other ingredients

-lubricates and protects epidermis

-inhibits bacteria

(body odor)

-found in armpits, around nipples and groin

-associated with hair follicles

-produce sticky, cloudy secretions

-brak down and cause odors

-widely distributed on body surface especialy on palms and soles

-cools skin, flushes microorganisms and harmful chemicals from skin

-protect the eardrum

-produce cerumen (earwax)

-made of dead cells packed with keratin

-metabolic disorders can change nail structure

-produced nail bed

Deep epidermal fold near the bone

-visible portion of the nail

-covers the nail bed

-keratin hardening

-the pale crescent at the base of the nail

-dehydration

-electrolyte imbalance

(jelly fish)

-fluid filled cavity encircled by muscle fibers

-soft-bodied invertebrates

(cockroaches)

-body encased in hard shell chitin

-must be shed for growth

-limits body size as exoskeleton has to grow increasingly thicker and heavier

(People)

-rigid internal skeleton of bone to which muscles are attached

- SUPPORT

-STORAGE OF MINERALS

-STOREAGE OF LIPIDS

-BLOOD CELL PRODUCTION

-LEVERAGE

-shape

-internal tissues

-bone markings

-long and thin

-found in arms, legs, hands, feet, fingers and toes

-thin with parallel surface

-found in skull, sternum, ribs and scapula

-small irregular bones

-found between flat bones of the skull

-Have complex Shapes

-ex. small vertebrae and pelvic bones

-small and thick

-ex. ankle and wrist bones

-small and flat

-exists in a tendon

-develop inside tendons near joints of knees, hands and feet

-depression of grooves along bone surface

-projections where tendons and ligaments attach and at articulations with other bones

-tunnels where blood and nerve enter bone

-the shaft

-a heavy wall of compact bone, or dense bone

-a central space called marrow cavity

-wide part at each end and articulation with other bones

-mostly spongy bone

-covered with compact bone

-resembles a sandwich of spongy bone

-between two layers of compact bone

-no longer divide

-maintain bone matrix

-live in lacunae

-are between layers (lamellae) of matrix

-connect by cytoplasmic extensions through canaliculi in lamelle

-maintain protein and mineral conent of matrix

-helps repair damaged bone

-Immature bone cells that secrete matrix compounds

-surrounded by bone become osteocytes

(goo)

-matrix produced by osteoblasts, but no yet calcified to form bone

-secrete acids and protein-digesting enzymes

-giant, multinucleate cells

-perform Ostolysis (BREAKING DOWN OF SKELETON)

-derived from stem cells that produce macrophages

Dissolve bone matrix and release store minerals

-(BREAKING DOWN OF SKELETON)

-mesenchymal stem cells that divide to produce osteoblasts

-are located in endosteum

-ASSIST IN FRACTURE REPAIR

-dense matrix, containing deposits of calcium salts and bone cells with lacunae organized around blood vessels

-matrix is very hard but brittle and inflexible

-good for compression but not bleeding

Osteon is the basic unit of mature compact bone

-osteocytes are arranged in concentric lamellae

-around a central canal containing blood vessels

-bring blood into bone

-perpendicular to the central canal

-carry blood vessels into bone and marrow

(rubber bands) (circumfrence of bones)

-lamellae wrapped around the long bone

-brings osteons together

-covers all bones except parts enclosed in joint capsules

-made up of an outer, fibrous layer and an inner cellular layer

Functions of Periosteum

1. Isolate bone from surrounding tissues

2. Provide a route for circulatory and nervous supply

3. Participate in bone growth and repair

1. an incomplete cellular layer:

-lines the marrow cavity

-covers trabeculae of spongy bones

-lines central canals

2. contains osteoblasts, osteoprogenitor cells, and osteoclasts

3. is active in bone growth and repair

-no osteons

-matrix forms an open network of trabeculae

Intramembranous Ossification (dermal ossification

Endochonral Ossification