ch. 33 coelomates mollusca Flashcards
phylum of protostomes
- phylum anthropoda
- phylum annelida
- phylum mollusca
subphylums of phylum anthropoda
- subphylum hexapoda
- subphylum myriapoda
- subphylum crustacea
- subphylum chelicerata
class of subphylum hexapoda
class insecta
class of subphylum myriapoda
- class symphyla
- class pauropoda
- class chilopoda
- class diplopoda
classes of subphylum crustacea
- class maxillopoda
- class malacostraca
- class branchiopoda
classes of subphylum chelicerata
class arachnida
classes of phylum annelida
- class Polychaeta
- class clittelata
classes of phylum mollusca
- class Cephalopoda
- class bivalvia
- class gastropoda
- class polyplacophor
phylum mollusca characteristics
- soft body
- protective external shell
- 3 body parts
- open circulatory system
- metanephridia
- radula
3 body parts of phylum mollusca
- foot
- visceral mass
- mantle
radula in mollusca
unique tongue-like organ
metanephridia
excretory gland
radere
to scrape
sexuality of molluscs
- separate sexes
- gonads located in visceral mass
- external fertilization
- include ciliated trochophore
polyplacophora
- 8 dorsal plates
- foot acts as suction cup, nearly impossible to pry if off rocks
poly
many
placo
plate
ex. of class bivalvia
clams, mussels, oysters
how do gastropods move
inch along by rippling motion of elongated foot
how do terrestrial snails perform gas exchange
lack gills, so use vascular mantle cavity
characteristics of class bivalvia
- shells divided into 2 halves
- adductor muscle draws 2 halves tightly together
- no head
- gills for feeding and gas exchange
- complete gut
- open circulatory system
ex. of polyplacophora
chitons
ex. of gastropoda
snails, slugs, nudibranchs, abalone, limpets
what is the largest class of protostomes
class gastropoda
characteristics of Gastropoda
- shells can be reduced or lost
- most marine or freshwater, some colonized land
where are eyes located in gastropoda
tips of tentacles
how are bivalvia anchored when shell is open
extends its hatchet-shaped foot for motility
how can scallops move about
by clapping its valves
how do bivalvia take in food
- food particles trapped in mucus on gills
- use cilia to move food into mouth
fresh water flow through bivalvia
fresh water flows in through incurrent siphon, over gills, then out through excurrent siphon
ex. of cephalopoda
octopuses, squids, nautiluses, cuttlefish
characteristics of cephalopoda
- fast-swimming marine predators
- closed circulatory system
- beaklike jaw
- change color
- well-developed brain/nervous system
where is the coelom in mollusca
small area around heart
