Integumentary System Flashcards
Comprised of skin or integument, hypodermis and structures derived from skin
Integumentary System
Superficial layer (skin composition)
Epidermis
Other term for hypodermis
Subcutis
Located in the stratum basale of epidermis
ovoid cell with long axis parallel to basal lamina
Merkell cells
deeper layer
dermis
- Most numerous cell type
- produces keratin
Keratinocytes
Pigment producing cells
Melanocytes
round or ovoid nucleus with cytoplasm containing ovoid pigment granules
Melanosomes
Melanosomes + tyrosinase?
Melanin
Dark brown pigment
Eumelanin
Yellow red pigment
Pheomelanin
stellate with long cytoplasmic processes, from bone marrown, with related functions to monocytes and macrophages
Intraepidermal macrophages
- outermost layer of the epidermis
- several layers of dead keratinocytes
Stratum corneum
present in skin epidermis and keratined or cornified mucous membranes
soft keratin
skin appendages
contain large amounts of cystine and disulfide bonds
hard keratin
not typically present in the skin of domestic animals except in:
digital pads
perioplic epidermis
teat
Stratum lucidum
account for the clear appearance of stratum lucidum
Eleidin
mitosis is not possible in this layer
start of the process of keratinization
stratum granulosum
contain kertohyalin granules
keratinocytes
part of stratum germinavitivum
Stratum spinosum
deepest layer of the epidermis that lies over the dermis
has a wavy apperance
Stratum basale
Stratum basale + stratum spinosum?
Stratum germinativum
- in contact with the stratum basale separated by basal lamina
- presents dermal papillae
- contains sensory receptors and capillaries
Papillary layer
- deeper and main part of the dermis
- irregular DWFCT with thick bundles of interlacing collagen fibers
- also with sweat and sebacous glands
Reticular layer
hypodermal fat in marine mammals
blubber
in other areas of the body
Paniiculus adiposus
carnivore footpad and horse sole
Digital cushion
thinnest skin in the body
scrotum
simple coiled tubular apocrine sweat glands that open to the surface of the skin or into the hair follicle
external auditory meatus
combination of sebum, secretion of ceruminous gland and desquamated epithelial cells
cerumen or ear wax
- structures derived from the skin
- from epidermis to hypodermis
adnexa
covers the entire animal body except for hairless regions
Ordinary hair
contains natural pigment and moisture of hair
cortex
core of hair
medulla
outer layer of hair shaft
cuticle
- large hair, associated with sensory nerve endings
- given off by tactile or sinus hair follicle
Sensory or tactile or sinus hair
diagonal band of smooth muscle cell, attached at the papillary layer of the dermis
Arrector pili muscle
inactive mammary gland
non-lactating mammary gland
active mammary gland
lactating mammary gland
only skin gland in bird
special sebaceous gland located above the sacral vertebra
uropygeal gland / preen gland / oil gland
