Lecture 10 - Integument part II Flashcards
What is dermis?
CT layer deep to epidermis
What lays inbetween the s. basale and the dermis?
Basement membrane
What is the function of the dermis?
Nourishes epidermis, highly vascularized
What are langer lines the purpose?
determines tension and wrinkles in skin lines
What are langer lines made of?
Pattern distribution of Type I collagen fibers
Why is it important to know where langer lines are?
determines pace and nature of wound healing
What are the layers of the dermis?
Papillary and reticular
What is the papillary layer made up of?
loose connective tissue
How does it interact with the epidermis?
Interdigitates with epi. still seperated by basement membrane
What are the interdigitations between the epidermis and dermis called?
Rete apparatus
What fibers are with in the papillary layer?
Collagen fibers (I and III), elastic fibers, and anchoring fibers
Where are the anchoring fibers originating from?
Basal lamina
What is the reticular layer made from?
Dense irregular connective tissue
What fiber types are with in the reticular layer?
Type I collagen fiber and thick elastic fibers
What other cell types are with in the reticular layer?
smooth muscle cells
What is the purpose of smooth muscle cells with in the reticular layer?
arrector pilli
What other structures reside within the reticular layer?
Epidermally derived glands and hair follicles
What is a first degree burn?
just epidermis destroyed
What is a second degree burn?
Epidermis + dermis are destroyed (blistering)
What is a third degree burn?
Epidermis + dermis + hypodermis
What are considered appendages of the skin?
Claws, nails, hair, sweat glands, and sebaceous glands
What is hair made of?
elongated keratinized structures derived from invaginations of epidermal epithelium
What causes shedding?
An increased turn over rate of hair
What is a claw composed of?
Plate of keratinized epithelial cells
What do sebaceous glands produce?
sebum, waxy texture
Where are there no sebaceous glands?
Palms, soles, and sides of feet
Where are sebaceous glands located?
within fibrous sheath surrounding each hair folicle
Why might sebaceous glands be around hair follicles?
aid in hair flexability and proper skin texture
What else is grouped with sebaceous glands and hair follicles?
arrector pilli muscles
What is sebum made up of?
cholesterol, triglycerides, anf cell debris
What method of secretion do sebaceous glands use?
Holocrine
What happens with holocrine secretion?
as secretory cell matures, it dies and becomes part of secretory product
What is the acinus?
Basal layer of undifferentiated flattened epithelial cells resting on basal lamina
What do acinus cells have with in them?
Alot of lipid filled vacuoles
What are the two types of sweat glands?
Eccrine and apocrine
What is eccrine secretions used for?
temp regulation
What are apocrine secretions used for?
other uses (ie. temp regulation, sex glands)
What kind of gland structure is the eccrine gland?
simple coiled tubular glands
Where are eccrine glands located on dogs?
Tongue and foot pads
Where do these ducts open? What are they associated with?
On skin surface, out of sweat pores. Associated with nothing
What kind of secretion does eccrine do?
merocrine secretion
What is merocrine secretion?
excocytosis, cells are not damages during secretion
What is cytocrine secretion?
Cell not damaged but part of it gone
What do eccrine glands have to help move along secretions?
myepithelial cells
Where do apocrine glands come from?
Epithelium of hair folicle
What layer is the apocrine gland located in?
Dermis and hypodermis
Where are there always apocrine glands?
axilla, areola, and anal regions
What do dogs and cats use them for primarily?
thermoregulation
Where do apocrine glands open up?
just superficial to entry of the sebaceous gland
What do apocrine secretions contain?
pheromones
What is special about axillary apocrine glands?
secrete milky product, odorless until metabolized by bacteria
Which sweat gland is larger?
Apocrine gland
Where is the secretory product of apocrine glands stored?
lumen
