Integumentary system Flashcards
outer covering of the living tissues of insects;
composed of EPIDERMIS bounded by a BASEMENT MEMBRANE and on the outside by the CUTICLE
integument or body wall
produced by the epidermis;
restricts water loss;
lines the AIR TUBES, SALIVARY GLANDS, AND ALIMENTARY TRACT
cuticle
thin outer layer (3 to 0.1mu);
permeable to chemicals and nutrients but impermeable to enzymes;
deeply folded but later straighten after ecdysis
epicuticle
insects swallow air
ecdysis
layers of epicuticle
homogenous layer;
cuticulin layers (critical in the growth process);
wax;
cement
innermost layer fo the epicuticle
homogenous layer
long hydrocarbon chain
wax
tanned protein with lipids serving as a varnish like covering
cement
thicker layer;
forms the exuvium;
gives the cuticle strength and resilience;
formed of chitin (C18 H13 NO5)
exocuticle
is a nitrogenous polysaccharide linked to a protein
chitin
composed of mucopolysaccharide secreted by hemocytes;
run the nerves and tracheoles
basement membrane
multicellular with undifferentiated epidermal cells
spines
multicellular with specialized cells
setae / macrotrichia / trichoid sensilla
unicellular in origin
acanthae
subcellular
microtrichia
sense much of the insects tactile environment
setae
large setae
bristles / chaetae
cell for hair formation
trichogen cell
cell for socket formation
tormogen cell
functions of the integumentary system
provide rigid foundation for the body;
serves as point of attachment of muscles;
protect internal organs;
prevents dessication
molted skin
exuviae
triggered by hormones released when an growth reaches physical limits of the exoskeleton;
casting of the old cuticle
molting
separation of cuticle form the epidermis;
physical separation of epidermis form old endocuticle
apolysis
actual process of shedding off of the old skin
ecdysis
fills the resulting gap with an inactive molting fluid
epidermal cells
insulates and protects the EC from molting fluid’s digestive action
cuticulin layer
exo and endo cuticle
PROCUTICLE
line the pore canals for the water retention and water loss mechanism
wax
allow movement of lipids and protein toward the new epicuticle
pore canals
where wax and cement layer form
epicuticle
lines of weakness in the old epidermis
ecdysial sutures
shedding of old skin
ecdysis
processes by which the new cuticle are made more resistant to degradation, more stiffer, and less soluble
sclerotization / tanning
tanning substances for the cuticle from tyrosine in the hemolymph
quinones
controls sclerotization
bursicon
hardening without the development of a new color
b - sclerotization
hardening with colors
quinone sclerotization
insect actively constructs new exoskeleton
pharate condition
a condition on where the insect is newly molted, and is soft and unpigmented
teneral condition
triggers the epidermal cells to change in number and size
ecdysone
necessary for cuticle tanning and endocuticle formation
bursicon
induce sclerotization in ligated abdomen of blowfly larvae
ecdepteroids
produce as a result of tanning in the outer part of the procuticle to form the exocuticle
rigid cuticle
the chitinous cuticle as it is 1st secreted is known as _________
procuticle
inner undifferentiated part of the cuticle
endocuticle
the sclerites are joined by _____________
flexible arthroidal membranes
colorless, rubberlike protein
resilin
