Integumentary Flashcards
The two major layers of the skin
Epidermis
Dermis
The largest organ of the whole body and forms a water resistant/water proof covering over the entire surface of the body
The skin
The epidermis is classified as:
Stratified squamous epithelium
* no blood supply
Five layers of cells that form the epidermis
Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum germinativum
One cell layer thick. cells are perfectly formed. This is the germinating (growing) layer. The cells are continually dividing and the new cells are pushed up to the surface to replace those, which are worn away. Pigment granules, which determine the color of the skin, are present in this layer.
Stratum germinativum
Name of the pigment granules in the skin
Melanin
There are no blood vessels and very few nerve endings in what?
The epidermis
The basal layer is made up of which layers
Stratum germinativum
Stratum spinosum
The primary site of cell division/reproduction (mitosis) in the skin. It is the layer cells are made. The deepest layer in the epidermis and is in contact with the dermis directly beneath it.
Basal layer
How many days does it take for cells to move up the five layers of the epidermis before being shed ?
28-42 days
Know as prickle cell layer in the epidermis in this layer the cells are living. The cells interlock by arm like threads, which give the cells a prickly appearance. Pigment granules may be found here. Cells develop desmosomes.
Stratum spinosum
A layer of soft cells
Prickle cell layer
Also known as the granular layer. Keratin begins to invade cells. The thickness of this layer can vary from one cell thick to several cells thick and is most dense on soles of the feet and palms of hands
Stratum granulosum
As the cells die they fill with tiny granules called?
Keratohyalin
The change of living cells into dead, horny, flat cells with no nucleus
Keratinization
Also known as the clear layer - the cells in this layer have lost their nucleus and have a clear appearance. The cells are transparent, which allows the passage of sunlight into the deepest layers. This layer is only found on the fingertips, the palms of the hands and soles of feet
Stratum lucidum
Known as the horny layer - the uppermost layer is made up of flattened dead scale - primary concern of estheticians. The keratinized cells help to prevent bacteria entering through the skin and protect the body from major injury. Cells are continually being rubbed off by friction and are being replaced by cells from the layer beneath
Stratum corneum
The shedding of dead skin cells
Desquamation
The natural loss of water by constant gentle evaporation through our skin is what?
TEWL - Trans Epidermal Water Loss
Water makes up to _________% of the weight of the basal layer, but only _________% of the stratum corneum
70-75%
10-15%
Which layer is a very important layer in understanding skin, skin problems, skin care and the beneficial effects of cosmetics and skin care preparations. It has a big role in helping to contain moisture within the rest of the skin. Under normal condition up to 15% of it consist of water. Less than 10% will cause dehydrated skin prone to damage, breakdown, and infection.
Stratum corneum
In the epidermis the spaces between the cells are packed with what?
Fats or lipids made by the body.
One very important group of lipids. Also ingredients of some skin care products.
Ceramides
Dryness
Desiccation
Important for getting rid of old skin cells
Natural enzymes
” true skin” is made up of fibrous and elastic connective tissue and blood vessels. Also contains white collagen fibers and yellow elastic tissue. 25 times thicker than epidermis. Support structure
The dermis
Yellow elastic tissue
Elastin
Plumps the skin
Collagen
Keeps skin supple
Elastin
What are the two parts of the dermis
Papillary layer
Reticular layer
Intercellular connections. Assist in strengthening and holding cells together.
Desmosomes
Keratin is formed by cells called?
Keratinocytes
1 in every 5 to 10 stratum germinativum cells are what?
Melanocytes
Melanocytes are cells which produce?
Melanin
Upper 1/5 of dermis - very thin. Connects dermis to epidermis. Contains pain and touch receptors and capillaries that feeds stratum germinativum. Membrane of ridges and grooves that make our fingerprints.
Papillary layer
Attaches the skin to the underlying tissues and organs. It consist primarily of loose connective tissue and adipose tissue. It protects the muscles, bones and internal organs from being damaged.
Subcutaneous layer
Serves as a heat insulator and a storage site of excess nutrients
Subcutaneous adipose tissue
A group of similar cells is ________.
Tissues
Name the four major groups of tissues. State each function.
Epithelial - covering, lining
Connective - connects and insulates
Muscles - movement
Nerve - transmit information electro-chemical signals.
State the shapes of epithelial tissues.
Squamous
Columnar
Cuboidal
Transitional
State the function of goblet cells.
Produces mucous to lubricate and protect
What cell stores lipids in the body
Adipocytes
What type of forms protein fibers in the connective tissues
Fibroblast
State the two primary supportive connective tissue types
Cartilage and bones
Immature cartilage cells are termed
Chondroblast
Mature bone cells are termed
Osteocytes
What is the matrix of blood
Plasma
What is the functional cell in nervous tissue
Neurons (receive and transmit electro-chemical signals)
Which vitamins are fat soluble
A,D,E,K
Name the vitamin necessary for blood clot formation
Vitamin K
List the nutrients needed for tissue repair
Proteins
carbohydrates
Vitamins A,B,C,D,E,K
A deficiency of this vitamin can prevent even superficial healing
Vitamin C
Which cells help with tissue repair which results in scar formation
Stroma
Which cells help with tissue repair which is nearly perfect
Parenchyma
What is the study of the tissues called?
Histology
What is the study of the skin
Dermatology
List the general functions of the skin?
Secretion Heat regulation Absorption Protection Excretion Sensation
The skin secretes sebum from the sebaceous glands. This fatty substance lubricates the hair shafts and when combined with perspiration on the surface of the skin, it creates a natural moisturizer, which acts as a protective barrier against bacteria
Secretion
Nerves control the state of the skins blood vessels by two actions:
Dilation
Constriction
The organs involved in heat production
Muscles
Liver
Digestive organs
Name two different types of sweat glands?
Eccrine
Apocrine
The sweat gland attached to the hair follicle
Apocrine
Perspiration is a secretion discharged directly onto the surface of the skin by which glands?
Eccrine sweat glands
What is the primary function of melanin?
To protect the deeper layers of the skin from damage
What type of tissue is the skin made up of?
Stratified squamous epithelial tissue
Keratin, a fibrous protein, would be found most abundantly in which layer of the epidermis?
Stratum corneum
The layer of the epidermis (skin) where the skin is thick, that can only be found on the palms of the hands and soles of the feet?
Stratum luciderm
The pigment produced by melanocytes is called? What layer are these cells found?
Melanin. Stratum germinativum, stratum spinosum, (basal layer)
How does melanin prevent skin damage from U.V. Light?
The more melanin the harder it is for rays to reach the dermis. Absorbs harmful rays and stops them from penetrating into body
What will excessive exposure to U.V. Light result in?
Damage to the DNA in the cells in the Basal layers
Melanocytes begin producing melanin when they are exposed to what?
UV light
Natural body odor is produced by the ________ glands
Apocrine
Helps with premature aging and hydration. Found in reticular layer
Hyaluronic acid
How long does the desquamation process take?
2-3 weeks for children and infants
4-6 weeks for people in 20s
6-8 weeks for 40s - 60s
What does the sebaceous glands secrete?
These are the oil glands- they secrete an oil called sebum
List the appendages found in the dermis
Arrector muscles Blood vessels Hair follicles Nerve endings Sebaceous glands Sudoriferous - sweat glands
