Postlab 4 - Integument Flashcards
Functions of the integumentary system
- protective wrapping
- regulatory function
- information getting
- excretory function
- respiratory function
- survival
- behavioral interactions between individuals
- mechanical protection against abrasion and puncture
- effective barrier against bacteria
- moisture proofing against loss or gain
- protective underlying cells against UV
protective wrapping
temperature regulation
regulatory and excretory function
sensory receptors
information getting
nourishment of the young
survival
Two layers of the skin
- epidermis
- dermis
- outer layer
- with nonliving coverings in craniates
- granular, avascular
epidermis
outer layer in fishes
mucus
- outer layer in terrestrial craniates
- dead and water-impervious cornified cells
- minimizes water loss
stratum corneum
secretes irritating or toxic alkaloids and many pheromones
granular glands
musous glands on the digits of tree frogs
holdfast
restrains female during copulation in male anurans
swollen mucous glands on thumb pads
extensive __ produces a prominent cornified layer
keratinization
__ __ and the __ incorporated in the skin prevents dessication
- cornified layer
- lipid
Different epidermal layers
- stratum corneum
- stratum lucidum
- stratum granulosum
- stratum spinosum
- stratum basale
connects the epidermis and the dermis
basement membrane
Types of epidermal glands
- mucous glands
- granular glands
- avian oil glands
- sebaceous / oil glands
- sudoriferous / sweat glands
has practically disapperead among terrestrial tetrapods except in mammals
mucous glands
- secrete irritating or toxic alkaloids for defense or pheromones
- restricted to a localized area of the body
- toads and reptiles
granular glands
granular glands in toads
parotid gland
- located at the base of the tail behind the pygostyle
- secretes a ipid and protein products that birds collect on the sides of their beak and then smear on their feathers during preening making them water repelland
uropygial gland
where is the uropygial gland found
behind pygostyle
- alveolar glands with oily secretions
- secretion is released into hair follicles in order to condition and help waterproof the fur
sebaceous / oil glands
secretions of sebaceous glands
sebum
produce a watery product (perspiration or sweat)
sudoriferous / sweat glands
- protection agains abrasion
- offense and defense
- adjunt of thermoregulation
stratum corneum
Specialized stratum corneum
- scales
- claws
- horny protuberances
- hair
- feathers
- repetitious thickenings of the stratum corneum found only in amniotes
- squamates
epidermal scales
stratum corneum disposed on overlapping folds of the epidermis
squamates (snakes, lizards)
large, thin, quadrilateral or polygonal scales
scutes
scutes of turtles
thick plastron
thinner carapace
where do epidermal scales develop in birds
where there are no feathers (facial area, legs, feet)
have hair and scales interspersed over the entire body
armadillos
where are scales in mammals found
legs and tails
inner layer of scales of lizards and snakes
deposited
outer layer of scales of lizards and snakes
shed at next molt (ecdysis)
ecdysis lizards
large patches
ecdysis snakes
outer layer of entire body
modifications of the stratum corneum at the ends of the digits
claws, hooks, nails
parts of claw, hooks, nails
- unguis
- subunguis
- cuneus
horny dorsal plate
unguis
softer ventral plate
subunguis
calluslie, cornified; ungulates
cuneus
having hoofs; of or belonging to a former group of all mammals having hoofs.
ungulates
wrap partially around the terminal phalanx
- unguis
- subunguis
- basal amniotes, birds, and most mammals
- curved and laterally compressed keratinized projections from the tips of the digits
- protects the tips of the digits from mechanical injury
claws or talons
digits of the wings
talons
- plates are highly packed, keratinized cells
- protection, scratching, and manipulation
- formed by cells in matrix
nails
cuticle
eponychium
- enlarged keratinized plates at the tips of the ungulate digits
- thick unguis of a hoof is U or V shaped which consists of dead cells
hooves
- distinguish birds from all other vertebrates
- nonvascular and nonnervous products of the epidermis and keratinizing system
feathers
Morphological varieties of feathers
- contour feather
- down feather (plumules)
- hairlike feathers (filoplumes)
gives the bird its contour or general shape
contour feather
parts of the contour feather
- shaft
- calamus (quill)
- rachis
- vane
- superior umbilicus
- afterfeather
- inferior umbilicus
horny part of feather
shaft
vane bearing
rachis
flattened
vane
- smooth erector muscles inserted on the walls of feather follicles
- with extrinsic integumentary muscles, it enable a bird to fluff its feathers
arrectores plumarum
distinctive tracts
pterylae
where is pterylae absent
- ostriches
- penguins
- small, fluffy feather lying underneath and between contour feathers
- short calamus
- crown of barbs w/o hooklets
down feather (plumules)
down feather (plumules)
- short calamus
- crown of barbs w/o hooklets
- shaft have a few barbs and associated barbules at the tip
- follicles are richly supplied with tactile nerve endings
hairlike feather (filoplumes)
follicles of filoplumes are richly supplied with what?
tactile nerve endings
- screen eyes, ear and nasal openings of foreign matter
- around the mouth are tactile receptors
- w/o terminal barbs
- head and neck
bristles
epidermal growths that function in protection
hairs
main parts of hair
- shaft
- root
- follicle
found around the hair
- sebaceous gland
- arrector pili muscle
- hair root plexus (touch)
insulators
fur
sensitive tactile organs
vibrissae
Different types of fur
- guard hair
- underfur
large, coarse hairs and found on the outer surface of the fur
guard hairs
beneath the guard hairs and usually much finer and shorter
underfur
Morphology of the hair
- root
- shaft
- cuticle
- hair cortex
- hair medulla
- base of the hair
- hair cells are cornifying and dying
- not separated from the follicular wall
root
remaining length of hair
shaft
What does a single hair have
- dense keratin
- air vacuoles
- melanin granules
- smooth muscle inserted on the wall of each hair follicle
- makes the hair stand erect in response to cold, fear, or anger
arrector pili muscle
- found only in mammals
- composed of skina nd underlying bone
- organs of offense, defense and display
horns and antlers
- surface is composed of keratin
- associated integument produces tough, cornified sheat that fits over the bony core
horns
- simple unbranched structures that are never shed
- found in males and females
bovine horns (true horns)
have true horns
Artiodactyls of family Bovidae
branched and the horny covering is shed annually
pronghorns
- composd of agglutinated keratinized hairlike epidermal fibers that form a solid horn perched on a roughened area of the nasal bone
- present in both sexes and are not shed
hair horn
- overlying living skin shapes and provides vascular supply to the growing bone
- not cornified structure but dermal bone attached to the frontal lobe
- only in males except in reindeer and caribou
- shedding is under hormonal control
antlers
overlying living skin
velvet
have antlers
Family Cervidae (deer, elk, moose)
animals that have antlers in female
- reindeer
- caribou
- resemble stunted antlers
- short bony projections of the frontal bones
- remain in velvet throughout life
giraffe horns
- seies of keratinized plates that arise from the integument
- act as strainers to extract food from water gulped by the animal
- seen in mysticete whales
Baleen or whalebone
where are baleen or whalebone found
mysticete whales
Other cornified structures
- rattles
- beaks
- rooster’s comb
- ischial callosities
- knee pads
- tori
- corns and calluses
rings of horny stratum corneum that remain after each molt
rattles
covered with horny sheath
beak
covered with a thick, warty stratum corneum
rooster’s comb
Hard, bare “sitting pads” on the buttocks
ischial callosities
found in camels
knee pads
apical pads in cats
tori
are thick, hardened layers of skin that develop when the skin tries to protect itself against friction or pressure
Corns and calluses
- dense connective tissue layer, contiains blood vessels, collagenous fibers, nerves, pigment cells, fat cells, and fibroblasts
- support, cushion, and nourish the epidermis
- macrophages and lymphocytes
dermis
two major regions of the dermis
- papillary layer
- reticular layer
- upper dermal region
- dermal papillae
papillary layer
deepest skin layer
reticular layer
primitive fishes
- ostracoderms and placoderms
- hagfishes and lampreys
integument produced prominent bony plates or dermal armor that encased their bodies in an exoskeleton
ostracoderms and placoderms
dermal bone is lost and the skin is smooth and without scales
hagfishes and lampreys
- dermal bone is absent
- covered with placoid scales
chondrichthyes (cartilaginous fishes)
scales in chondrichthyes (cartilaginous fishes)
placoid scales
dermis composed of the superficial loose connective tissue and a deeper layer of dense fibrous connective tissue
bony fishes
Types of scales in bony fishes
- cosmoid scales
- ganoid scales
- teleost scales
- in primitive sarcopterygians
- composed of thick, well developed layer of dentine beneath a thin layer of enamel
cosmoid scales
where are cosmoid scales found
sarcopterygians
- with thick surface coat of enamel and with an underlying layer of dentin
- dermal bone forms the foundation
ganoid scales
forms the foundation of ganoid scales
dermal bone
where are ganoid scales found
- Garke
- Sturgeon scutes
- lacks enamel, dentin and a vascular bone
- with lamellar bone which is acellular and mostly non-calcified
teleost scales
two types of teleost scales
- cycloid scale
- ctenoid scale
composed of concentric rings
cycloid scales
with a fringe of projections along its posterior margin
ctenoid scales