Chapter 5 - Integumentary System
Terms in this set (33)
Outermost layer of skin. No blood supply.
Middle layer of skin. Deep, connective tissue and contains blood vessels, glands and hair follicles
Deepest and thickest layer of skin. Blood supply
What are the four cell types of the epidermis?
Keratinocytes, melanocytes, langerhans, merkel cells
Cell of epidermis. Produce tough, fibrous, waterproof protein called keratin. Gives skin resiliency and strength
Cell type of epidermis. Produces melanin
Cell of epidermis. Originates in bone marrow. Help stimulate aspects of immune system
Cell of epidermis. Aid in sensation of touch
Process of keratinization
New cells are produced and push older ones away from life-sustaining dermis and toward outer layers of epidermis. They become lifeless sheets of keratin and rub or exfoliate off the skin daily.
Layers of epidermis
Stratum Basale, Stratum Spinosum, Stratum Granulosum, Stratum, Lucidum, Stratum Corneum
Stratum Germinativum (Basale)
Deepest layer of epidermis. Consists of single row of keratinocytes that are firmly attached to the epithelial membrane
2nd layer of epidermis. "Spiny layer". Cells contract into sea urchin-like masses. Contains several layers of cells that are held together by desmosomes.
Middle layer of epidermis. 2-4 layers of flattened, diamond shaped keratinocytes. This layer aids in waterproofing skin
Clear layer of epidermis. Only found in very thick skin such as paw pads. Located beneath Corneum.
Outermost layer of epidermis. Cells are anucleated and keratinized.
Middle layer of skin. Deep, connective tissue portion of the skin that contains blood vessels, glands, and hair follicles
Layers of the Dermis
Papillary layer and reticular layer
Top layer of Dermis. Loose connective tissue that is adjoined with the epidermis
Deep layer of the dermis. Irregular connective tissue and makes up the majority of the dermis
What are the two structures of the hypodermis?
Meissner's corpuscle: sensitive to light and touch
Pacinian corpuscle: sensitive to heavier pressure
Dark brown and found on the inside of each leg at the carpus(knee) of the fore arm and the tarsus/hock of the hind leg
Vestiges of the 2nd and 4th digits. Horn like growths located behind the fetlocks of all equids.
Tops of cats, dogs, pigs, sheep's nose. 3 epidermal layers
What are the three cycles of hair growth called?
Anagen, catagen, telogen
(Active phase, transitional, resting phase)
What determines hair color?
Pigment in the cortex and medulla gives hair it's color. Melanocytes located at the base of hair follicle
What are the three types of hair called?
Straight, arched, thicker and longer than secondary hairs. Dominant hairs in complex hair follicle
Secondary/ wool-type hairs
Softer and shorter than primary hairs. Wavy and bristled
Tactile/ sinus hairs
Probes, feelers, whiskers
Arrector Pili Muscles
Small, smooth muscles attached to each hair follicle that erect when animal is frightened or cold
What are the two types of sweat glands?
Eccrine and apocrine
Secrete substances directly onto skin without loss of cellular material
Secretions contain some of it's cellular material. Secrete into the hair follicle, not onto skin