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