exam #2 Flashcards
(33 cards)
nematode amphids
paired lateral sensory organ derived of cilia
nematode cuticle
noncellular covering of collagen secreted by underlying epidermis
syncytial (nematode epidermis)
nuclei are not completely separated by cell membranes
eutely (nematode/rotifer)
growth increases in the size of cells, not by the number of cells
true circulatory system (nemertine)
blood circulates through well-defined contractile vessels
proboscis (nemertine)
retractable muscle that is distinct from digestive tract, located in the rhynchocoel, and used to capture prey as it can be shot out
rhynchocoel (nemertine)
fluid-filled, has circular muscles around it that can contract, and is used to shoot out the proboscis
pilidium larvae (nemertine)
long-lived, ciliated, swimming, and feeding individuals
imaginal discs
discrete masses of embryonic tissue within the pilidium larvae that are preprogrammed to form specific tissues/organs and eventually fuse together to form the juvenile organism
corona
2 ciliated areas surrounding the mouth which beat giving the impression that the lobes are rotating, can add to locomotion, but are mainly used for respiration and food collection by generating a current
mastax
the muscular modification of the pharynx that contains trophi
trophi (rotifer)
rigid jaw structures located within the mastax used to grind food for digestion to follow
toes (rotifer)
has adhesive glands
class seisonidea (rotifer)
ectoparasites of marine crustaceans, reproduction is sexual, and has a reduced corona since they rely on host for nutrients
class bdelloidea (rotifer)
free-living, mobile so well developed corona, reproduction through parthenogenesis, and live in stressful environments so exhibit cryptobiosis (cysts)
class monogononta (rotifer)
most rotifers, free swimming (younger) and sessile (settle to plants when older), some produce a lorca, and some sessile have spines on corona to trap prey
lorca (rotifer)
protective tube constructed of sand grains, mucus and fecal pellets
parthenogenesis (rotifer)
2n female produces 2n eggs via mitosis. unfertilized eggs develop into more 2n females, cycle continues unless harsh conditions which cause 1n eggs via meiosis causing a resting egg which are resistant to harsh conditions and are in a dormant state (diapause) and only hatch after conditions get better even it is years later
cyclomorphosis (rotifer)
induced phenotypic plasticity in response to chemical cues
mantle (mollusk)
doors; epithelial (specialized tissue) that secretes shell or spicules
periostracum (mullusk)
thin outer organic layer of shell
nacreous layer (mollusk)
thin, innermost calcareous layer of shell
prismatic layer (mollusk)
thick calcareous middle layer of shell
radula (mollusk)
a rasping “tongue” with chitin teeth and sometimes also a chitinous jaw
