skin glands Flashcards
two types of skin glands
-sebaceous
-sweat
2 types of sweat glands
-eccrine
-apocrine
what are skin glands modifications of
the epidermis
sebaceous glands are associated with
hair follicles
structure of sebaceous glands
lobed (acinar) structure
what do sebaceous glands produce and what is the function of this
-they produce fatty/oily sebum (lanolin in sheep)
-moisturises and waterproofs hair and skin
-allows sweat to spread (thermoregulation)
-antimicrobial function
-pheromones or other scented compounds for communication
circumoral sebaceous glands in cats
round the nose and mouth for scent marking and greeting
carpal glands
found on carpus of cats and dogs with tactile hairs
circumanal glands in dogs
under anal sac glands
sebaceous glands in the sheep
-infraorbital (by the eye)
-interdigital (in-between digits for trail marking)
-inguinal pouch (odour helps lamb find udder)
apocrine sweat glands
-discharge albuminous (protein-rich) sweat
-into hair follicles
-over most of body (haired skin) in domestic animals
-react with bacteria to produce an individuals odour
eccrine sweat glands
-discharge more watery sweat
-directly onto skin
-generally found only in certain areas (naked skin) eg- footpads
mode of cellular secretion for apocrine glands
-apocrine secretion
-vesicles pinch off from cells to secrete packets of cell membrane and cytoplasm
mode of cellular secretion eccrine sweat glands
-merocrine secretion
-exocytosis
-cell vesicle fuses with membrane to discharge its contents
-no part of the cell is lost
mode of cellular secretion eccrine sweat glands
-merocrine secretion
-exocytosis
-cell vesicle fuses with membrane to discharge its contents
-no part of the cell is lost
what are mammary glands modifications of
-apocrine sweat glands
aquired function of the mammary glands
- The secretion (milk) is rich in protein and fat for nourishing young
- contains antibodies for immune transfer
- First milk (colostrum) is especially rich in antibodies, important in immune transfer
mammary glands are made up of…
- a body (mammae) and teat
what are collections of mammary glands in horses and cattle called
udders
what does eac gland contain
one or more secretary unit
what are extra buds called
supernumerary teats (indépendant or attached to more developed glands)
teat orifice
the hole the milk comes out of
how is milk made
- Milk is produced by mammary cuboidal epithelial cells, lining alveoli (hollow cavities)
* Alveoli grouped into lobules joined by connective tissue
* Lobules are grouped into lobes, separated by adipose tissue - Alveoli are surrounded by muscle cells (myoepithelial cells) that push milk out of the alveolus
- Milk drains through milk ducts (lobular ducts →lactiferous ducts)
- milk is stored in the lactiferous sinus
-mostly within the teat (sinus)
-partly in the body (gland sinus) - A smooth muscle sphincter at the teat orifice prevents milk leakage and bacteria entry
- When properly stimulated, milk is “let down” under influence of hormones
* contraction of myoepithelial cells around alveoli
* relaxation of teat sphincter muscle
what ligament divides the left and right side of the mammary glands
median suspensory ligament
do birds have sweat glands
NOOOO
-loose heat by blood flow to skin
-respiritory evaporation (panting)
skin glands in birds
-lipogenic epidermis deposits lipid film onto feathers
-preen, aural, vent
skin glands in reptiles
-scent gland at the vent
-pre-fermoral glands/ femoral pores
skin glands in ferrets
-no sweat glands
-sebaceous glands in skin giving musky smell
-anal glands
guinea pig skin glands
caudal gland (‘grease gland”) used for marking territory
hamsters and gerbils skin glands
-flank scent glands
-ventral glands
skin glands rabbits
-scent glands (chin glands, inguinal glands, anal glands)
fish skin glands
-mucous glands (insulation, UV protection, reduce water friction)
-venom secretion
