Terms to Remember:

What is the Epidermis?

Superficial layer of the cutaneous membrane, consisting of 5 layers

What is the Dermis?

Deeper layer of cutaneous membrane, consisting of 2 layers

What is the hypodermis?

Subcutaneous layer that isn’t part of the integument

What are the layers of Epidermis from deep to superifical?

Stratum Basale, Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, and Stratum Corneum

What cells are found in the Stratum Basale?

Stem cell (divide), Melanocytes (melanin), and Merkel cells (sensory)

What cells are found in the Stratum Spinosum?

Keratinocytes and Dendritic cells (immune)

What cells are found in the Stratum Granulosum?

Flattened keratinocytes

What cells are found in the Stratum Lucidum?

Dead, flattened, keratinocytes (only in thick skin)

What cells are found in the Stratum Corneum?

Dead, flattened filled keratinocytes, shed every 7-10 days

What are Merkel Cells?

Sensory cells

What are Dendritic Cells?

Immune cells

What are the two layers of Dermis?

Papillary and Reticular

What tissue is the Papillary Layer made of?

Areolar tissue

What tissue is the Reticular Layer made of?

Irregular dense connective tissue

What is in the Papillary layer?

Capillaries, lymphatic vessels, and sensory neurons

Where can you find the subpapillary plexus?

In the Papillary layer of the dermis, (houses small artieries)

Where can you find the cutaneous plexus?

In the Reticular layer of the dermis, (house deeper network of arteries)

What is in the Reticular Layer?

Collagen and Elastic fibers making it flexible

What is a Skin Turgor and where is it located?

Loss of elastin in the dermis due to dehydration, aging, UV, or hormones

What makes a fingerprint?

The epidermal ridges and dermal papillae in the stratum basale

4 Functions of Epidermis?

Protection, Temp Regulation, Sensation, and Vitamin D production

What is insensible water loss?

Water loss that you cannot see (500mL a day)

What is sensible water loss?

Water excreted by sweat glands

What is a blister?

Fluid formation between superficial and deep layers of the epidermis

What is Xerosis?

Dry skin from insensible perspiration in the epidermis

What glands are located in the dermis?

Sebaceous, eccrine (merocrine), and apocrine

What are Pacinian (Lamellar) Corpuscle?

Deep pressure, vibration and touch cells in the dermis

What are Meissner (Tactile) Corpucle?

Light touch cells in the dermis

What is the function of Hypodermis?

Stabilze skin

What tissue is the hypodermis mainly composed of?

Adipose tissue (fat)

What injections take place in the Hypodermis?

Subcuteanous injections take place using hypodermic needles

What is the primary determinant of skin colorz?

Melanin

How is melanin produced?

By melanocytes

Why do some people have darker skin?

Because they have more melanin

What is Albinism?

genetic mutation lacking melanin

What is Freckles?

Irregular small pigments of melanin with irregular borders

What are Lentigos?

Similar to freckles but with regular borders, but have abnormal melanin

What are Senile Lentigos?

Liver spots, found in elder people with pale skin

What is Jaundice?

Bile not excreted by liver (yellow eyes)

What is Addision disease?

Caused by pituitary gland releasing ACTH

What is Vitiligo?

Autoimmune condition causing loss of skin pigment

How does the skin look with normal blood?

Blood flow increases oxygen = reddish look

What is Cyanosis?

Lack of oxygenation in blood = bluished skin

What is bronzed skin?

Increase of MSH causing a bronze look

What is Basal Cell Carcinoma?

Benign, flesh colored, perfect circle with a superficial lesion

What is Melanoma Cancer?

Mallignant (dangerous), abnormal borders with deep lesion, darker brown/black

What is Carotene?

Orange/yellow pigments from orange veggies

What can Carotene convert into?

Vitamin A for vision

What is Vitamin D also called?

Cholecalciferol

What convert Cholecaliferol?

The liver and kidney convert vitamin D into calcitriol

What does Calcitriol do?

Essential for absorption of calcium

Inadequate amount of Vitamin can cause?

Rickets in children and Osteomalacia in adults (soft, weak bones, bone pain, and deformitites)

Steps for Vitamin D?

1. Skin: UV converts into vitamin D

2. Liver and Kidney: converts vitamin D into calcitriol, active form of Vitamin D

3. Small intestine and bones absorb calcium and phosphorus to support bone mineralization

Where are accessory structures located?

In the dermis consisting of hair follicles, sebaecous glands, sweat glands, and nails

Where is a Hair Follicle located?

Deep into the dermis and sometimes the hypodermis

Whats the structure of hair?

base of hair is surround by sensory nerves (root hair plexus) to feel movement. Sebaceous gland is attached to the side releasing oils to the hair

What causes goosebumps?

Arrector pili muscles

What is Vellus hair?

soft, fine hair before puberty

What is terminal hair?

heavy, pigmented hair after puberty

What is a sebaceous gland?

Oil gland that secretes holorcrine (ruptures) sebum into hair follicles

What is a type of sebaceous gland/

Simple branched alveolar gland (hair follicle)

What is inflammation in repair of integument?

Bleeding, swelling, and pain occur. Mast cells trigger inflammatory response, and scab begins to form. Macrophages clean the area

What is a scab?

Fibrous protein that forms blood proteins

What is migration in integument repair?

Scar is formed stratum basale migrates along the edges of the wound

What is Proliferation is integument repair?

A week after injury scab has been undermined, by epidermal cells, migrating over the collagen fiber meshwork produced by fibroblast

What is Scarring in integument repair?

Several weeks after injury scab shedded epidermis is complete, fibroblast in the dermis continues to create a scar tissue that will gradually elevate

Whats a keloid?

Scar tissue formation continues beyond the repair of skin and therefore grows into the dermis

First degree burn?

Partial thickness burn, only epidermal, include sunbuyrn, skin redden, and can be painful

Second degree burn?

Partial thickness, entire epidermis and some dermis, blistering, pain and swelling

Third degree burn?

Full thickness burn, hypodermis to complete redness, less painful because nerves are killed, needs skin graft

Aging effects?

Epidermal thins (basal cells decline), blood supply to dermis is reduced, and dermis thins (wrinkling)

What is the Lunula?

Pale part near root of nail that is cut from blood supply

What are nails?

Protect against mechanical stress

What is a type of sweat gland?

Apocrine glands which secrete at puberty (odor) found in armpits, nipples, and pubic region

What are Eccrine (Merocrine) glands?

Discharge directly onto skin surface to cool the body and provide protection

Autograft

Skin taken from another area of the same person's body

Allograft (homograft)

Skin taken from another person,

Xeno Graft:

Different species donor, like pig skin to human

What are the steps to tissue repair?

Inflammation, Organization, Regeneration, and Fibrosis

What is inflammation?

Blood vessels widen and immune cells remove germs and bacteria

What is organization?

Blood clot form, new blood vessels and connective tissue begin to develop

What is regeneration?

New cells replace damaged cells with same tissue

What is Fibrosis?

Scar tissue forms when damaged tissue cannot fully replace itself

What are the symptoms that tissue repair is needed?

Redness, Heat, Swelling, and Pain

What are Aging signs?

Slow repair hormonal alterations, and reduced physical activity

Function of Epithelial tissue?

Protect, Secrete, Absorb, and Excrete

Functions of Connective tissue?

Bind, support, protect, fill spaces, and store fat

Functions of Muscle tissue?

Movement

Functions of Nervous Tissue?

Conduct impulses for coordination, regulation, and sensory regulation

What is Avascularity is Epithelial tissues?

No blood vessels, recieves nutrients via diffusion

What is Polarity is Epithelial tissues?

Apical surface and basal surface which attaches to basal lamina of basement membrane

What is Attachment is Epithelial tissues?

To basement membrane (basal + reticular lamina) via connective tissues

What is Cellularity is Epithelial tissues?

Intercellular junctions, tight packed

What is Regeneration is Epithelial tissues?

Regenerate easily

Function of spot desmosomes?

Tie cells together while still allowing them to bend and twist

Where are Spot desmosomes located?

Cardiac tissue, bladder, and lining of the intestine

Function of Hemidesmosomes?

Attaches to basement membrane to help stablize the position of the cell

Where are Hemidesmosomes located?

Basal surface of epithelial cells, skin epidermis, cornea, and esophagus

Function of Tight Junction?

Connection between cells formed by fusion of protein membrane, restrict movement

Location of Tight Junctions?

Digestive tract and Kidney Tubules