Pigmentation & Appendages of the Skin

Black

“Melanin” meaning

Melanin

Pigment found in eyes, skin, and hair

Increased melanin production

Exposure to sun =

The equator

Darker-skinned people tend to live near ___

Freckles and moles

Accumulations of melanin

Carotene

Found in carrots

Corneum

Carotene gets put in the stratum _____

No

Is carotene dangerous to health?

Vitamin A

What vitamin does Carotene turn into in the liver?

Hemoglobin

Oxygen carrying pigment found on red blood cells giving it is red color

Little melanin

Why does caucasian skin show color easier?

Hereditary factors

All people are born with the same number of melanocytes, but various melanin production

Environmental factors

Sunlight, UV rays, X Rays

Physiological factors

Jaundice, Carotene accumulation, vasodilation/constriction

Cyanosis

Poor oxygenation; occurs during heart failure and respiratory diseases

Redness (Erythema)

Capillaries dilate; can be caused by irritation or injury; or other things like embarrassment

Pallor or Blanching

Blood is shunted or directed from the surface; fear, anger, anemia, low blood pressure

Jaundice

Build up of yellow bile pigments from bilirubin; problems with liver

Vitiligo

Autoimmune disease; localized depigmentation; lack of melanocytes

XP and EPP

Rare genetic disorders where people are “allergic to the sun”

Hematoma

Another word for a bruise; collection of blood in a tissue caused by a break in a blood vessel

Appendages

Derivatives of the epidermis

Appendages

Nails, sweat glands, sebaceous glands, and hair

Epithelial tissue

What all glands are made up of

Simple cuboidal

What most sweat glands are

Sweat glands and salivary glands

Glands that are stratified only

Sudoriferous

Most numerous gland in the body

Nipples, lips, and few in genitalia

Where there are no sudoriferous glands

Deeper dermis

Where do sudoriferous glands originate

Eccrine and apocrine

Two types of sudoriferous glands

Sudoriferous glands

Simple, coiled tubular glands

Through a duct system (exocrine gland)

How do sudoriferous glands secrete

Eccrine sweat glands

Found almost everywhere and most numerous

An open pore on the skin

Where do eccrine sweat glands empty to

Body temperature

Eccrine glands regulate _________

Sweat from eccrine glands

99% is water, salts, antibodies, vitamin C, and some wastes; acidic pH

Apocrine sweat glands

Only found in axillary and groin areas; larger

Deeper in the dermis

Where are the apocrine glands located

Hair follicles

Where do apocrine ducts empty to

Sweat from apocrine glands

Fatty substances and proteins are added

Apocrine glands

Respond to emotion and pain

Ceruminous and mammary 

Specialized sudoriferous glands

Ceruminous gland

Modified sweat gland; ear wax (cerumen)

Earwax

Deters insects and blocks entry of foreign materials

Mammary glands

Secrete breastmilk

Sebaceous

Associated with the hair follicles; produces sebum (oil)

Sebum (oil)

Fatty material and cellular debris; softens and lubricates hair and skin; can kill bacteria

Acne

What does excess sebum cause

Vernit caseosa

Greasy deposit on the skin of a baby at birth; keeps good bacteria in, bad bacteria out

Hair

Flexible strands; usually large keratinized cells; melanocytes provide pigment

Palms, soles, lips, and nipples

Millions of hairs everywhere expect:

Not warmth; sensing insects on skin; protect head from trauma, heat, and sunlight; eyelashes shield eyes; nose hairs filter things

Functions of hair

Hair bulb

Made of dividing cells

Hair root

Remainder of follicle in the dermis

Hair shaft

Dead epidermal cells; protects from skin

Arrector pili

Smooth muscle; causes goose bumps; responds to fear and temperature

Problems with hair growth

Influenced by nutrition, hormones, and genetics

Hirsutism

Excessive hairiness due to ovarian or adrenal problems

Werewolf syndrome

Mutation of the X chromosome

Alopecia

Hair not replaced

Alopecia areata

Antibodies attack hair follicles

Trauma, surgery, drugs, and diet

What can also cause hair thinning and loss

Histology

Study of tissues

Tissues

“Hist”

Tissue

Groups of cells with similar structure and function

Covering

Job of epithelium tissue

Support

Job of connecting tissue

Control

Job of nervous tissue

Movement

Job of muscle tissue

Epithelial tissue

Covers external surfaces

Epithelial tissue

Lines internal organs and cavities

Epithelial tissue

Forms membranes

Epithelial tissue

Glandular tissue

Epithelial tissue

Forms the skin

Epithelial tissue

Absorption; villi of small intestine

Epithelial tissue

Filtration; in the kidneys

Epithelial tissue

Secretion; glands

Epithelial tissue

Cells fit closely together to form sheets

Apical

Free surface— no blood

Basal

Attaches to connective tissue— blood

Avascular

Does not have a direct blood supply

Simple

One layer; for absorption, secretion, and filtration

Stratitifed

More than one layer; helps in protection

Squamous

Flattened

Cuboidal

Cube shaped

Culumnar

Column like

Connective tissue

Most abundant and widely distributed of all tissue types

Bind/support; protect; insulate; transport substances

Functions of connective tissue

Extracellular matrix; variations in blood supply

What makes up connective tissue

Extracellular matrix

Nonliving material that surrounds the cell; mostly water

Variations in blood supply

Some tissues are well vasculated, some are avascular

Ground substance

Mostly composed of water

Fibers

Produced by the cells

Collagen (white)

Strongest and most abundant fiber

Elastic (yellow)

Yellow fiber

Reticular fibers

Type of fine collagen

Stratified squamous epithelial tissue

Top layer of skin is made up of what

Areolar

Top layer of the dermis is

Dense irregular

Bottom layer of the dermis is

Connected tissues

Areolar and dense irregular are