Lecture 5 - 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 fluid loss or gain
- protect underlying cells against UV
protective wrapping
temperature regulation
- regulatory function
- excretory function
sensory receptors
information getting
nourishment of the young
survival
one of the largest organs of the body
integument
the integument is __ of body weight
15%
separated by basal lamina
epidermis and dermis
epidermis and dermis are separated by what
basal lamina (ectoderm and endoderm, respectively)
- outer layer
- with nonliving coverings in craniates
epidermis
slippery, protects the fish from infection
mucus
- in teresstrial craniates
- dead and water-impervious cornified cells (minimizes water loss)
- grandular, avascular
stratum corneum
- single layer of mucus-secreting cells
- dermis with collagen
- pigment from epidermis
protochordate: skin of amphioxus
Fishes and Aquatic Amphibians
- epidermal glands
- photophores
- keratin
holds mucus
microridges
produces mucus and other substances
granular cells
- arise from pluripotent stem cells and derive their name from their goblet, cup-like appearance
- secrete mucin and create a protective mucus layer.
- also thought to be involved with immunoregulation
Goblet cells
functions of secretions in fishes
- repel predators
- prevents dessication during aestivation in summer
- nutritious mucous that serves as food for hatchlings
glands in aquatic amphibians
granular glands
secretes irritating or toxic alkaloids and many pheromones
granular glands
holdfast for tree frogs
mucous glands on digits
mating position of frogs and toads, in which the male clasps the female about the back
amplexus
- light emitting organs found in deep-sea teleosts
- arise in the epidermis and invades the dermis
- for species and sex recognition, lure or warning aid, concealment by countershading
photophores
example of organisms with photophores
midshipman
sclero-protein that is insoluble in water
keratin
keratin in fishes
little or no keratin
thin keratin serves to reduce water loss through the skin in dry terrestrial environments
aquatic urodeles
have cornified “teeth”
- hagfish
- lampray
epidermis of tetrapods
extensive keratinization
prevents dessication
- cornified layer
- lipid
Different Epidermal Layers
- stratum corneum
- stratum lucidum
- stratum granulosum
- stratum spinosum
- stratum basale
- stratum membrane
Types of epidermal glands
- mucous glands
- granular glands
- avian oil glands
- sebaceous glands
- sudoriferous (sweat) glands
- scent glands
- mammary glands
has practically disappeared 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
- found in toads and reptiles
- absent in birds and mammals
granular glands
where can granular glands be found
- toads
- reptiles
granular glands of toads
parotid gland - behind eyes
- secrete a substance that hardens to form temporary spines to restrain the female during copulation
- found in lizards
femoral glands
where are femoral glands found
lizards
secretes a lipid and protein product that birds collect on the sides of their beak and then smear on their feathers during preening, making them water repelland
avian oil glands
located at the base of the tail behind the pygostyle
uropygial gland
where can uropygial gland be found
base of tail behind pygostyle
- alveolar glands with oily secretion
- secretion is released into hair follicles in order to condition and help waterproof the fur
sebaceous/ oil glands
secreted by sebaceous glands
sebum
Glands under sebaceous glands
- ceruminous glands
- meibomian glands
- secretes cerumen or earwax and, together with the hair, trap foreign objects that might enter into the canal
- seeps out wax to keep the tympanic membrane soft, pliable, and waterproof
- found in the outer ear
ceruminous glands
secreted by ceruminous glands
cerumen or earwax
- found in the eyelid
- secretion assist in moistening the conjunctiva of the eye
meibomian glands
meibomian glands assis in moistening what part of the eye
conjunctiva
meibomian cyst
chalazion
produce a watery product (perspiration or sweat)
sudoriferous (sweat) glands
Two types of Sweat Glands
- eccrine
- apocrine
- produces thin sweat, not associated with hair follicles and function before puberty
- products function in regulation of body temperatuer
eccrine
- viscous sweat, associated with hair follicles, and begins functioning in puberty
- responsible for the “body odor”
apocrine
distribution of sweat glands:
chimpanzees and humans
greatest number, also in palms and soles
distribution of sweat glands:
duckbill platypus
snout
distribution of sweat glands:
deer
base of the tail
distribution of sweat glands:
mice, rats, and cats
paws
distribution of sweat glands:
rabbits
around lips
distribution of sweat glands:
elephant
absent
functions of sweat glands
- dissipate heat
- contains waste products thus for elimination of metabolic by-products
- produce secretion that play a part in social communication
- mark territory, identify the individual, communicate during courtship
scent glands
- skunks drive away enemies
- male musk deer signal sex
anal glands
swell during breeding season in male elephants
temporal glands
- function only in the female
- produce milk which is a water mixture of fats, carbohydrates, and proteins
mammary glands
cavity where milk can collect between two milkings
teat cistern
where do mammary glands develop from
milk lines
pair of elevated ribbons of ectoderm that extend along the ventrolateral body wall of the fetus from axilla to groin
milk lines
where do milk lines extend
along the ventrolateral body wall of fetus from axilla to groin
Distribution of mammary glands:
cats, dogs, pigs, rodents, edentates
- axially
- thoracic
- abdominal
- inguinal
Distribution of mammary glands:
insectivors, some lemurs
- one thoracic pair
- one inguinal pair
Distribution of mammary glands:
monkey, apes, humans
thoracic
Distribution of mammary glands:
cetaceans, dolphins
single pair near the groin
Distribution of mammary glands:
nutrias, otters
four nipples at the back
during pregnancy, what is formed at the ends of the branching duct system
enormous numbers of alveoli
cluster of scretory alveoli in which milk is produced
lobule
common chamber where alveolar duct open into
cistern
forms secondary duct carrying milk from the cistern to the surface
teats
what is build up beneath the mammary glands to produce breast
adipose tissue
- nipples and teats are absent and breast fo not form
- milk is released from ducts onto flattened milk patch or areola on the surface of the skin
monotremes
- protection against abrasion
- offense and defense
- adjunct of thermoreguation
- specializations - scales, claws, horny protruberances, hair, feather
stratum corneum
repetitious thickening of the stratum corneum found only in amniotes
epidermal scales
stratum corneum disposed on overlapping folds of the epidermis
squamates (snakes and lizards)
formed basically by integument folding in many aquatic and terrestrial vertebrates
scales
folding of ossified dermal bone
dermal scale
folding of thickened epidermal keratinized layer
epidermal scale
large, thin, quadrilateral or polygonal scales
scutes
scutes of turtles
- thick scutes (plastron)
- thinner on carapace
- epidermal scales develop where there are no feathers
- facial area, legs, feet
birds
have hair and scales interspersed over the entire body
armadillos
scales in legs and tails
mammals
inner layer
deposited
outer layer
shed at next molt
the act of molting or shedding an outer cuticular layer
ecdysis
ecdysis in lizards
large patches
ecdysis in snakes
outer layer of the entire body
modifications of the stratum corneum at the ends of the digits
claws, hooks, and nails
parts of claws, hooks, and nails
- unguis
- subunguis
- cuneus
horny dorsal plate
unguis
softer ventral plate
subunguis
- calluslike, cornified
- ungulates
cuneus
where do unguis and subunguis wrap around
terminal phalanx
- curved and laterally compressed keratinized projections from the tips of the digits
- basal amniote, birds, and most mammals
claws or talons
- plates of highly packed, keratinized cells
- protection, scratching, and manipulation
nails
growth of nails
1mm per week
area of specialised skin cells on the ventral side of the proximal nail fold that produce the cuticle
eponychium
eponychium
cuticle
white area at the base of a fingernail
lunula
Parts of the nail
- free edge
- nail body
- lunula
- eponychium (cuticle)
- nail root
- nail matrix
- enlarged keratinized plates at the tips of the ungulate digits
- U or V shaped which consists of dead cells
hooves
thick __ of a hoof is U or V shaped which consits of dead cells
unguis
- distinguis birds from all other vertebrates
- nonvascular and non-nervous products of the epidermis and keratinizing system
feathers
develop in the dermis in the breast of some birsd with increased vascularizaiton for incubating eggs
brood patch
Morphological varieties of feathers
- contour feather
- down feather (plumules)
- hairlike feather (filoplumes)
gives the bird its contour or general shape
contour feather
parts of a contour feather
- shaft
- calamus
- rachis
- vane
horny; made of rachis and calamus
shaft
quill
calamus
vane bearing
rachis
flattened superior umbilicus afterfeather inferior umbilicus
vane
- smooth erector muscles inserted on the walls of the feather follicles
- with extrinsc integumentary muscles enable a bird to fluff its feathers
Arrectores plumarum
- distinctive tracts
- absent in ostriches and penguins
pterylae
- small, fluffy feathers lying underneath and between contour feathers
- short calamus
- crown of barbs without hook
- for insulation
down feathers (plumules)
what are down feathers (plumules) for
insulation
- shaft and a few barbs
- associated barbules at the tip
- follicles are richly supplied with tactile nerve endings
hairlike feather (filoplumes)
- without terminal barbs
- found in the head and neck
- screen eyes, ear and nasal openings of foreign matter
- acts as tactile receptors aroung the mouth
bristles
what happens to old feathers
molted
what happens to new feathers
grows out of follicle by cell proliferation
feather that is complete with all parts to function
mature feather
- epidermal growths that function in protection
- made up of shaft, root, and follicle
hairs
parts of the hair
- shaft
- root
- follicle
what is found around the hari
- sebaceous glands
- arrector pili muscle
- hair root plexus (touch)
hair acts as insulator
fur
hair act as sensitive tactile organ
vibrissae
different kinds of fur
- guard fur
- 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
rooted in the dermis but is produced within the epidermis projecting out above the surface of skin
hair follicle
small tuft of dermis
hair papilla
the germinal region that does the process of keratinization producing hair within the follicle
matrix cells
contribute pigment granules
chromatophores
thin band of smooth muscle anchored in the dermis and attached to the follicle
arrector pili muscle
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
single hair
- dense keratin
- air vacuoles
- melanin granules
present in hair that is laid out in a particular direction
grain
- holds the mucus in fetus
- beings int he 3rd month
lanugo hair
lanugo hair are __ hair; they are thin, fine hair that grows on most of your body
Vellus
shape of hair follicle:
wavy hair
oval
shape of hair follicle:
curly or kinky
flat and ribbon like
shape of hair follicle:
straight
round
- found only in mammals
- composed of skin and the underlying bone
- organs of offense, defense, and display
horns and antlers
- surface is composed of keratin
- associated integument produces tough, cornified sheath that fits over the bony core
- found in males and females
horns
branched and the horny covering is shed annually
pronghorns
- overlying living skin (velet) 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
supplies nutrients and minerals to the growing bone.
velvet
- resemble stunted antlers
- short bony projections of the frontal bones
- remain in velvet throughout life
giraffe horns
- series 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
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
beaks
covered with a thick, warty stratum corneum
Rooster’s comb
found in monkeys and apes
ischial callosities
found in camels
knee pads
found in cats
tori (apical pads)
- dense connective tissue layer, containd blood vessels, collagenous fibers, nerves, pigment cells, fat cells, and fibroblasts
- support, cushion, and nourish the epidermis
- macrophages and lymphocytes
dermis
layer in the dermis
- papillary layer
- reticular layer
- upper dermal region
- uneven and has finger-like projections from its superior surface
papillary layer
- indent the epidermis above
- capillary loops, which furnish nutrients to the epidermis
dermal papillae
what does the papillary layer house
- pain receptors
- touch receptors (Meissner’s corpuscles)
involved in skin movement and object handling detection, and their primary stimulation is through dynamic deformation
Meissner corpuscles
primarily sense skin stretching, movement, and finger position
Ruffini corpuscles
- sense vibrations and detect fine textures.
- deep pressure
Pacinian corpuscles
function of fingerprints
- increase friction
- enhance gripping ability of fingers and feet
- deepest skin layer
- blood vessels, sweat and oil glands, deep pressure receptors
- have phagocytes
reticular layer
prevent bacteria that have managed to get through the epidermis from penetrating any deeper into the body
phagocytes
integument produced prominent bony plates or dermal armor that encased their bodies in an exoskeleton
- ostracoderms
- placoderms
dermal bone is lost and the skin is smooth and without scales
- hagfish
- lamprays
- cartilagenous fishes
- dermal bone is absent
- covered with placoid scales
chondrichthyes
chondrichthyes or cartilagenous fishes are covered with what
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 of this
ganoid scales
forms the foundation of ganoid scales
dermal bone
- 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 scales
- ctenoid scales
composed of concentric rings
cycloid scales
with a fringe of projections along its posterior margin
ctenoid scales
make up the shell of the turtle
bony plates
