Week 8 Flashcards
what are the four levels of organismal complexity?
protoplasmic, cellular, tissue and organ system
what is the phylum porifera
sponges!
The porifera skeleton is made up of _______-
spicules
what are asconoids
flagellated spongocoels
what are choanocytes
in all sponges, cells with flagella that help make a water current to pull water in
what are syconoids
wall contains folded back choanocyte lined canals, spongocoel lined with epithelial cells
what are leuconoids
clusters of flagellated chambers, no spongocoels, have many exits
what are the support cells in sponges
choanocytes, pinacocytes and archaeocytes
what are pinacocytes
can open or close of the surface and can control gas exchange, flow of water, etc
what are archaeocytes
can transport particles around the sponge, food to other cells, help make up the skeleton
what are collencytes
secrete collagen, make web like structure within cytoplasm, create skeletal sort of structure
how do sponges reproduce asexually
by fragmentation or budding
how do sponges reproduce sexually
internal and external fertilization, produces free swimming larva
T or F: most sponges monoecious
T
what are the three classes of sponges
calcarea, hexactinellida and demospongiae
what is the class homocleromorpha
originally thought to be part of demospongiae, grows on rocks
what is class calcarea
have straight spicules, tend to be small
what is class hexactinellida
usually six rayed, deep sea forms
what is class demospongiae
80 percent of all spongiae, wide variety of types
what are the four characteristics echnioderms have that no other phylum does
1-endoskeleton of ossicles
2-water vascular system
3-pedicelariae
4-pentaradial symmetry
ossicles are plates made out of _____
calcium
how does the water vascular system work
water comes in through pore, flows through radial canal an through tube feet in order to cause movement
what are pedicellaria
jaw-like pincers on the surface, like forceps, some capture food particles, others for protection, keep animal clean
pentaradial symmetry has __ lines of symmetry
5
what is class asteroidea
sea stars
T or F: class asteroidea is capable of regenerating
T
what is class ophiruoidea
brittle stars
T or F: brittle stars’ tube feet lack suckers
T
what is class echinoidea
sea urchins and sand dollars
sea urchins have ___ symmetry
radial
sand dollars have ___ symmetry
bilateral
what is the class holothuroidea
sea cucumbers
what is the class crinoidea
sea lillies and feather stars
what is the difference between sea lillies and feather stars
sea lillies are anchored, whereas feather stars have arms and are freemoving
what is the synapomorphy between homalozoa and other echnioderms
water vascular system
what is the synapomorphy between helicoplacoidea and other echnioderns
pentaradial symmetry
what is the synapomorphy betweeen crinoidea and other echnioderms
madreporite on aboral surface
what is the synapomorphy between asteroidea and other classes
closed ambularcral grooves
what are some characteristics of the phylum hemichordata
gill slits, dorsal nerve cord, no notochord or postanal tail,
what are two synapomorphies of echniodermata and other deurterostomes
dorsal hollow nerve cord and pharyngeral gill slits
what are three synapomorphies of other deuterostomes and chordates
notochord, postanal taiol, and endostyle
what are the four deuterostome traits
enterocoel, mesoderm derived from archenteron, mouth not derived from blastopore, coelom tripartite
