coelom
a fluid-filled cavity that separates the ectoderm from the endoderm
foot
large mass of muscle at base of organism, chief locomotor structure of molluscs
visceral mass
the region where most internal organs are contained including the external gill
mantle
specialized epidermis that includes envelopes all visceral mass and secretes shells
gills
respiratory structures formed by the mantle
radula
tongue-like organ with chitinous ornamentation
chromatophores
special pigment cells that contain pigments in the skin
iridophores, leucophores
reflect light and can make blue, green, and white
metamerism
series of body structures that are similar internally and externally such as segments (true segmentation)
teloblastic growth
the segments behind the head arise sequentially from a growth region anterior to the pygidium (tail)
clitellum
a reproductive structure that generates mucus to aid sperm transfer and also produces a "cocoon," within which fertilization occurs
setae
Chitinous bristles that are anchored in the epidermis and provide traction
chitin
forms a protective armor outside the epidermis
renette cells
the excretory cells unique to nematodes
molting
physiological process that all anthropods periodically go through
ecdysis
follows the molting process, the actual shedding of the exoskeleton
tagmata
discrete body regions/segments with different functions
hemocoel
bloody cavity
chelicerae
modified first pair of appendages that often serve as specialized clawlike or fanglike mouthparts
pedipalps
second pair of appendages that may also be used for general sensing the environment as well as the manipulation of food
pheromones
external chemical signals
water vascular system
consists of a central ring canal and radial canals that extend along each arm
tube feet
-Extensions of an echinoderm's water vascular system that stick out from the body \n -function as tactile and ambulatory structures
ampullae
controls individual tube feet
notochord
a flexible, rod-shaped mesodermal structure that is found in the embryonic stage of all chordates and in the adult stage of some chordate species \n -becomes intervertebrate discs in vertebrates
dorsal hollow nerve cord
-derived from ectoderm that rolls into a hollow tube during development \n -lost in urochordates
pharyngeal gill slits
-openings in the pharynx (the region just posterior to the mouth) that extend to the outside environment \n -used for filter feeding in aquatic chordates \n -only present in embryonic stage of tetrapods
post-anal tail
a posterior elongation of the body, extending beyond the anus
vertebrae
a series of separate, irregularly shaped bones joined together to form a backbone
gnathostomes
animals that possess jaws
tetrapods
four-footed animals
ganglia
mass of neurons in a centralized nervous system
hydrostatic skeleton
fluid within the coelom provide support for muscles to move against
protostomes
blastopore develops into the mouth
Deuterostomes
blastopore develops into the anus
jointed appendages
muscles are attached to jointed cuticle of the arthropods, make movement possible
spiracles
pores on the body of an insect that allow for gas exchange
aquatic crustacean gas exchange organs
gills
eusocial
organism population in which the role of each organism is specialized and not all of the organisms will reproduce
pentaradial symmetry
radial symmetry in multiples of 5
Echinodermata larvae symmetry
bilateral
endoskeleton
internal skeleton for protection and support made from calcium carbonate
water vascular system
A system of fluid-filled tubes in an echinoderm's body. \n -Extends down each arm, ending in tubed feet that have tactile and movement functions