Marine Bio Ch. 8
Give an example of symbiosis between a sponge and another organism
A sponge provides protection and sunlit habitat for the Cyanobacteria, and the Cyanobacteria provides the sponge with nutrients and oxygen
Define sessile
Animals that are permanently attached to a solid surface
What advantages does bilateral symmetry offer to animals like flatworms?
Bilateral symmetry allows for a more streamlined body shape and offers more advantages for animals with active lifestyles than radial symmetry. The streamlined body creates less drag when moving through the watery environment, and thus less energy is required for movement.
Define cephalization
Cephalization is the concentration of sensory organs in the head region of an animal
How is radial symmetry particularly helpful to sessile organisms?
Radial symmetry is particularly beneficial to sessile organisms and organisms that are not active swimmers because it allows them to meet and respond to their environment equally well from each side
How do some sponges compete with corals for substrate territory?
Sponges compete with coral so they can find enough solid material for attachment. Some sponge species produce chemicals that either kill corals or inhibit their growth
What do sponges feed on, and how has this led to their success?
Sponges feed on material that is suspended in sea water. This has led to their success because very few animals can capture food this size
How are sponges protected from predators?
Very few animals feed on sponges, possibly because ingesting the spicules would be like eating a mouthful of needles. Many sponges produce chemicals that prevent organisms from settling on their surface or that deter grazing
How have larger sponges overcome the problems of water flow and surface area?
Water enters a sponges body through the Ostia and eventually flows into a spacious cavity called the spongocoel. Water then exits the spongocoel through a large opening called the osculum.
