Porifera

Question 1

what are some body grades of Porifera

Answer 1

ascon
sycon
leucon

Question 2

what are some characteristics of porifera

Answer 2

body has pores canals and chambers
no true tissues or organs
no gut or nervous system
loosly aggregated cells
high regeneration capacity
sessile and marine
asymmetrical or radial
chambers lined with flagellated cells
internal structure of spicules or organic fibers

Question 3

what are some cell types of porifera

Answer 3

choanocytes
pinacoderms
mesohyl
porocyte

Question 4

what are the two sections of a choanocyte

Answer 4

flagellum and collar (arf)

Question 5

what are the categories of spicule and what are some examples

Answer 5

megascleres
style
calthrops
oxea

microscleres
sigmas
toxa
raphide

Question 6

what functions do spicules perform

Answer 6

structural support as well as defense

Question 7

what is the name of the reporductive structure and then specialised cell that transfers the sperm into the egg

Answer 7

oocyte and transfer choanocyte

Question 8

what are the classes of porifera

Answer 8

calcarea
hexactinellida
demospongiae
homoscleromorpha

Question 9

what are some features of calcerea porifera

Answer 9

spicules composed of calcium carbonate
all grades of body organisation
shallow marine dwellers

Question 10

what are some features of hexactinellida porifera

Answer 10

sillica spicules
spicules include 6 pointed hexagons that are fused to form lattice
generally syconoid form
mostly deep sea(400-900)
prominent in antartic waters

Question 11

what are some features of demospongiae porifera

Answer 11

includes 95% of sponges
skeleton may be spicules or spongin fibers or both
body organisation is leuconoid
found in deep sea and shallow environments
few freshwater species

Question 12

what are some features of homoscleromorpha porifera

Answer 12

small number of species in two families
separate from demosponges based on molecular and morphological differences
simple structure with spicules small or absent

Question 13

what are the two main growth forms of sponges

Answer 13

solid and tubular

Question 14

why are oscula raised above surrounding surface

Answer 14

improves passive water flow

Question 15

what is the bernoulli effect

Answer 15

where water flowing over the sponge is accelerated as it passes the oscula, causing a pressure drop, leading to water being dragged out of sponge