J.2 Sponges ( Phylum porifera)

what are the simplest animals

sponges

what phylum do sponges belong to?

proifera

What does "Porifera" mean?

Pore-bearing.

What type of body plan do sponges have?

Sac-like body plan.

What type of symmetry do sponges usually have?

Asymmetrical or radial symmetry.

Are sponges sessile or mobile?

sessile

Are sponges hermaphroditic?

yes

Do sponges have cephalization?

no

Where do most sponges live?

Attached to surfaces in warm ocean water.

What is the central cavity of a sponge called?

The spongocoel.

What are ostia?

Small pores where water enters the sponge.

What is another name for ostia?

Incurrent openings.

What are porocytes?

Pore cells that form and regulate the ostia

What is the function of porocytes?

Control the amount of water entering the sponge.

What is the osculum?

: The opening through which water leaves the sponge.

What is another name for the osculum?

A: Excurrent opening.

Trace the path of water through a sponge.

Ostia → Spongocoel → Osculum

What specialized cells line the inside of the sponge?

Choanocytes

What is the function of choanocytes?

Capture food and oxygen from incoming water.

How do sponges obtain food?

Filter feeding.

How does respiration occur in sponges?

Diffusion.

How does circulation occur in sponges?

Diffusion.

How do sponges remove wastes?

Wastes diffuse into the water flowing through the sponge.

What are amoebocytes?

Cells that produce support structures.

What hard support structures do amoebocytes produce?

Spicules.

What materials can form spicules?

Calcium carbonate or silicon dioxide.

What flexible support material can amoebocytes produce?

spongin

What are spongin fibers made of?

Protein.

Which support structure is rigid?

Spicules.

Which support structure is flexible?

Spongin fibers.

Why don't dried sponges rot?

Their shape is maintained by spicules or spongin fibers.

How do sponges avoid self-fertilization?

Sperm and ova mature at different times.

Which cells produce sperm in sponges?

amoebocytes

how are sperm released

Through the osculum into the water.

How does fertilization occur in sponges?

Sperm enter another sponge through water flow and fertilize ova.

What forms after fertilization?

A zygote.

What develops from the zygote?

A ciliated larva.

What is the function of the ciliated larva?

Swim away and establish a new sponge.

What is regeneration?

The ability to regrow damaged or missing body parts.

What is budding?

Production of a small packet of cells that grows into a new sponge.

What are gemmules?

Asexually produced spore-like structures.

when are gemmules produced

during favourable environmental conditions

how do gemmules leave the sponge

through the outgoing water

do sponges have true tissues

no

Why are sponges considered simple animals?

Their cells function independently and do not form tissues.

How do sponge cells communicate?

mainly through movement of molecules