Lab 3 Flashcards
______ and ______ are supporting structures/fibres in sponges
Spicules Spongin
What are these? What are they made of? What cells produce them?
Sponge spicules. Made of calcium carbonate or silica, come from sclerocyte cells
What is spongin? What cells produce this?
Collagenous protein fibres that support the skeleton of sponges. Produced by spongocytes
_____ are the narrow openings in for water inflow in sponges
Ostia
______ are the larger openings for water outflow in sponges
Oscula
Most sponge species are of _____ construction
Leuconoid
Describe water circulation in asconoid sponges. Where are the choanocytes located?
In through small ostia (chambers through porocytes) and out through a large oscula at the top or the sponge. Choanocytes line the spongocoel
What are the three sponge body plans (list in order of increasing complexity)? Briefly describe how they fundamentally differ
Asconoid, syconoid, leuconoid. Basically they just have increasing degrees of invagination of the choanocyte layer away from the spongocoel
The inner body cavity of the sponge is known as the _____
Spongocoel
List the phylum, class, and genus of this organism. What type of sponge is it? Describe water circulation in this type of sponge. Where are the choanocytes located?
Phylum - Porifera
Class - Calcarea
Genus - Sycon
Syconoid sponge! Water enters through small Ostia (chambers) into bulbous pockets lined with choanocytes. Water leaves through a large hole in the top of the sponge called the syconoid
Describe water circulation in leuconoid sponges. Where are the choanocytes located?
Water enters through small Ostia and flows through many paths in the sponge, hitting chambers lined with choanocytes (water may pass many chambers) before flowing out of one of a few oscula at the top of the sponge
Why must asconoid sponges be small?
Because the body cavity is lined with a single layer of choanocytes, and large asconoid sponges would not be able to filter fast enough to support themselves
What are the advantages leuconoid sponges have over syconoid sponges?
Water may pass several choanocyte chambers before being expelled - higher chance for filtration
Why are choanocytes essential for the life of sponges?
They are the only cells specialized for feeding in sponges, so without them they would not be able to sustain themselves
Briefly describe class Calcarea of the sponges
Contains the only living asconoids, bear calcium carbonate spicules, very small, contain members of all three sponge types
List the phylum, class, and genus of this sponge (seen through dissecting scope). What is the body plan of this sponge? Where are the choanocytes located?
Phylum - Porifera
Class - Calcarea
Genus - Leucosolenia
Asconoid. Located in the body cavity (spongocoel)
Briefly describe class Demospongiae
Contains at least 90% of living sponge species, skeleton composed of spongin and/or siliceous spicules, all leuconoid
Name the phylum, class, and genus of this organism.
What type of sponge is this? What is the composition of it’s skeleton? Where are the choanocytes located?
Phylum - Porifera
Class - Demospongiae
Genus - Spongia
Leuconoid sponge.
Madeof Siliceous spicules and spongin
Choanocytes located in the choanocyte chambers