40 terms

Skin & Hair Definitions

a layer of the skin or epidermis
scarf skin--the outer surface of skin visible to the eye
Stratum Corneum
horny layer—flat dead keratonized skin cells that form a protective layer on the surface of the skin.
Stratum Lucidum
clear layer—found only on area of the body where no hair follicles are, such as palms and soles.
Stratum Gransulosum
granual layer where cells are filled with keratohyalin, which helps form keratin. Eleiden is present
Stratum Spinosum
prickle cell layer—cells appear to have little spines on the outside of the membrane.
a tough fibrous protein that is part of the other layer of the skin's epidermis, hair, and fingernails.
True skin--below the epidermis. Composed mostly of elastin and collagen. Connective tissue foundation of the skin. Many nerve endings, hair follicles, glands are here.
Papillary layer
the upper sublayer of the dermis. Composed of cone like projections responsible for ID markings...finger prints.
Reticular layer
the lower sublayer of the dermis
large long chain molecular proteins that lie on the top of the skin and bind water. Also helps to prevent water loss
Elastic Fibril
is intertwine throughout the reticular layer of dermis and give skin firmness and elasticity
Subcutaneous Layer
the fatty layer of the skin found under the dermis..adipose
Sudoriferous Glands
sweat glands
Eccrine Glands
common smaller coiled sweat glands found all over the body. Have their own orifice, duct and fundus. Excrete water and salt like substance. Regulates body temperature
Appocrin Glands
larger coiled sweat glands located in groin and armpits. Produce thicker form of sweat responsible for producing the substance that when in contact with bacteria produces odor
Sebaceous Glands
multi lobed oil glands found in the dermis
a semi liquid oil secreted by the sebaceous gland to lub skin. Also acts as an insulator
a dark pigment found in the skin and hair. Produces melanocytes (pigment cells)
Arrector Pili Muscle
involuntary muscle attached to the hair follicle at an obtuse angle. Reacts to sensation of cold and fright.
Vellus Hair
soft downy type hair found everywhere on the body
Terminal Hair
deep seated course hairs which grow from the scalp, underarms, pubic region and other parts
Hair follicle
a pore like indentation of the skin from shich the hair grows
Hair Shaft
the portion of the hair above the skin surface
the portion of the hair which lies beneath the skin in the follicle
Dermal Papilla
a separate organ that supplies blood and other element essential for hair growth. Cells make up the Medulla of the hair
Hair bulb
enlarge base of the hair root
lower part of the hair bulb where cells begin Mitotic activity. Cells make up the Cortex of the hair
Connective Tissue "sheath"
a continuation of the dermis that surrounds the follicle and sebaceous glands and provides nerve endings and blood supply
Outer Root Sheath
a continuation of the Stratum Malpighii. It surrounds the Inner Root Sheath
Inner Root Sheath
Made up of Cuticle, Huxley, and Henle's Layer. Surrounds the hair as far up as the sebaceous gland ducts
Cuticle Layer of the IRS
Innermost layer of the Inner Root Sheath that Interlocks with the cuticle of the hair
Huxley's layer
middle and thickest layer of the Inner Root Sheath
Henle's layer
Outermost layer of the Inner Root Sheath
Cuticle of the Hair
Outermost layer of the hair that interlocks with the IRS anchoring the hair in the follicle.
Cortex of the hair
Middle layer, Matrix responsible for this layer, elongated cells
Medulla of the hair
innermost center layer of the hair, Dermal Papillae is responsible for this layer
active or growing stage
Transitional stage--lower half of the follicle degenerates
resting stage of growth