Chapter 1 A & P Key Terms Flashcards
Integumentary system
The skin and it’s accessory organs, such as the sebaceous and sweat glands, sensory receptors, hair and nails
Pilosebaceous unit
The entire hair appendage, including the sebaceous gland and the arrector pili muscle
Stratum Germinativum
The lower level of the epidermis where cell division occurs (mitosis)
Epithelial tissue
The tissue that forms a thin protective layer on bodily surfaces
Connective tissue
Fibrous tissue that binds protects cushions and supports the various parts of the body
Epidermis
The thin, outermost layer of the skin
Stratified epithelium
Layers of tissue that lack blood vessels; acts as a surface barrier
Keratin
A protein found in the skin that helps guard against invasion
Keratinization
The change of living cells to dead ones
Horny zone
The outermost portion of the epidermis
Germinal zone
The layer of skin where cells divide
Stratum corneum
Outermost layer of dead skin cells
Sebum
Fatty or oil section of the sebaceous gland that lubricates the hair and skin
Stratum lucidum
Clear; transparent layer of the epidermis; found under the stratum corneum
Eleidin
Clear, lifeless matter deposited in the form of minute keratohyalin granules in the protoplasm of living cells
Keratohyalin granules
Granules found in living cells that contribute to the keratin content of dead, cornified cells
Stratum granulosum
The granular layer of skin found at the bottom of the horny zone
Basal zone
Live layer of dividing cells that continuously change and pushed upward
Stratum Spinosum
The superior layer of the stratum germinativum; named for its shape and spiny, thorn like protrusions; also known as the prickle cell layer
Stratum basale
Single cell layer that is the deepest layer of the epidermis
Mitosis
The process by which a cell divides into two daughter cells
Desquamation
The act of exfoliating dead skin cells
Melanocytes
Melanin forming cells
Amino acid
Units of structure in protein that help breakdown simple sugars and fats
Tyrosine
An amino acid present in melanocytes
Melanin
Grains of pigment that give hair and skin its color
Stratum Mucosum
Single cell layer of the epidermis; found above the stratum germinativum
Malpighian
A single layer made of the stratum mucosum and the stratum germinativum
Dermis
Underlying or inner layer of the skin
Papillary layer
The most superficial layer of the dermis
Reticular layer
A deep layer of the dermis; composed of dense bundles of collagen fibers; contains vessels, glance, nerve, endings, and follicles
Dermal papilla
Small cone shaped indentation at the base of the hair follicle that fits into the hair bulb; also called the hair papilla
Collegenous
Fiber made of proteins that gives skin its form and strength
Papillae
Cone shaped, finger like projections that protrude into the epidermidis
Meissner’s corpuscles
Nerve endings in the skin that are sensitive to touch
Subcutaneous tissue
The fatty layer beneath the dermis that gives the body smoothness and contour; contains fat as an energy source and acts as a protective cushion for the outer skin; also cold, adipose or subcutis tissue
Lymph
Colorless, watery fluid that circulates through the lymphatic system; similar in composition to blood plasma
Apocrine
Glands in the axillae and groin that secrete sweat and substances that produce body odor when contaminated with bacteria
Axillae
Underarms
Pheromones
Chemicals produced by humans and other animals, that one secreted influence other members of the same species
Eccrine
Glands throughout the skin that excrete mainly water and salt
Sebaceous glands
Oil glands of the skin connected to hair follicles
Pacinian’s corpuscles
Nerve endings found deep in the skin that are receptive to pressure
Terminal hair
Hair found on the scalp, arms, legs, axillae, and pubic area post puberty
Arrector pili
An appendage that is attached to the dermal papilla and to the hair shaft
Adipose tissue
Connective tissue, in animal bodies that contains fat
Follicular canal
The depression in the skin the houses the entire pilosebaceous unit
External root sheath
The inner side of the follicular canal, which is made of horny epidermal tissue
Hair matrix
The germinating center of the hair follicle where mitotic activity occurs
Hair follicle bulb
The bulbous base of the hair follicle that houses the dermal papilla
Internal root sheath
The innermost layer of the hair follicle, closest to the hair
Cuticle
The outer most layer of hair consisting of one overlapping layer of transparent, scale like cells
Cortex
The middle layer of the hair; a fibrous protein core formed by elongated cells containing melanin
Medulla
The innermost layer of hair; composed of round cells; often absent in fine hair
Lanugo
Soft downy hair present on fetuses, in utero, and infants at birth
Vellus
Fine short hair with no pigment found mainly on women’s faces; Peachfuzz
Anagen
The growth phase in the hair cycle in which a new hair is synthesized
Catagen
The transition stage of the hair growth cycle; the period between the growth and resting phases
Telogen
The resting phase of the hair follicle in its growth cycle
Club hair
Hair that has lost its root structure, and that when shed from the follicle exhibits a round shape
Excretion
The act of discharging waste matter from tissues or organs
Secretion
The process of producing and discharging substances from glands
Absorption
The uptake of one substance into another
Acid mantle
Bacteria, killing layer made of sweat and lipids
Langerhans’ Cells
Cells found in the epidermidis that warn against the invasion of micro organisms and respond to that invasion
Leucocytes
White blood cells or corpuscles
Subcutis
A layer of subcutaneous tissue
Lymphocytes
Cells produced in the lymph nodes, spleen, and thymus gland that produces antibodies capable of attacking infection
Dilation
The process of widening or expanding
Constriction
The process of narrowing
Sudoriferous glands
The skins sweat glands
Cosmeceuticals
Products that form between the categories of pharmaceuticals and cosmetics, and the generally have a higher level of absorption and standard cosmetics
