[LBBBIO8] Activity 10 Part 2

Phylum Porifera

• Latin for pore-beraing

  • Porus = Pores

  • Fera = Bearing

• Lowest forms of multicellular animals

  • Neither true tissues nor organs are present

• Bodies made up of a loose aggregation of independent cells

  • Perforated by cells and canal systems

    • Lined with flagellated cells

  • Embedded in gelatinous matrix and stiffened by spicules of calcium carbonate or solica and collagen

• Aquatic organisms

Sessile

Stationary and attached to submerged suitable substratum

Water current

For metabolism

Asexually

Reproduction by budding, fragmentation, regeneration, and gemmule formation

Sexually

Reproduction by fertilization, forming free-swimming ciliated larvae

Taxonomy

• Diagnostic tool

• Based on the details of their endoskeleton (internal skeleton)

Skeleton

Consists of calcareous or siliceous crystalline spicules, spongin fibers made up of protein OR both

Spongocoel

Cavity

Ostia

Small pores

Osculum

Excurrent pores

Choanocytes

• Flagella of collar cells

• Allows circulation of water and minerals inside the canal

Asconoid (Simplest)

Choanocytes at cavity

Syconoid (Intermediate)

Choanocytes in radial canals

Leuconoid (Most complex)

Choanocytes in chambers

Class Calcarea

• SPICULES: Calcium carbonate

• Needle-shaped, 3 or 4 rayed

• Marine dwellers

Grantia

(Class Calcarea)

• Solitary

• Syconoid type

• Resembles a slender vase that bulges slightly near the center

• Wall of the cylinder has incurrent and radial canal

  • Lie alternately and readily around spongocoel

Osculum

(Grantia)

Opens at the exterior at distal end

Monoaxon Spicules

(Grantia)

Spicules of grantia

Ostia

(Grantia)

Surface of the cylinders

Spongocoel

(Grantia)

Inside each cylinder

Incurrent and radial canals

(Grantia)

Wall of the cylinder has these and they lie alternately & readily around spongocoel

Leucosolenia

(Class Calcarea)

• On the rocks near the seashores, below low-tide mark

• Asconoid type

Stolon

(Leucosolenia)

Stem where slender, tubular individuals grow in groups

• Attached to objects in shallow seawater

Osculum

(Leucosolenia)

Each tubes opens at the summit by means of it

Spongocoel

(Leucosolenia)

Cavity of the tube

Ostia

(Leucosolenia)
Smaller pores

Three-pronged (triradiate) Spicules

(Leucosolenia)

Spicules embedded in the soft tissue of the body wall

Class Hexactinellida

• Glass sponges

• Siliceous, six-rayed spicules

• Flagellated radial canals or chambers

• Syconoid or leuconoid arrangement

• Marine species (Most are deep-sea dwellers)

Eupectella

(Class Hexactinellida)

• Bottom of deep sea water

Spongocoel

(Eupectella)

Long, curved, cylindrical body (Tubular body)

Connecting ledges of spicules

(Eupectella)

It’s continuous in the body and can form a lattice network

Class Demospongiae

• Skeleton: Siliceous spicules that are not six-rayed or spongin fibers OR both

• Leuconoid type

• 1 family is found in freshwater and the rest are marine dwellers

Spongia

(Class Demospongiae)

• Commercial bath sponge

• Globose or hemispherical in shape

• Colonial

• Skeleton: Complex network of spongin fibers arranged in anastomosing pattern

• Attached to rocks in tropical and subtropical seas

No spicules

(Spongia)

Spicules

Oscula

(Spongia)

Seen on the surface

Ostia

(Spongia)

Smaller opening that beset oscula

Carteriospongia

(Class Demospongiae)

• Broad leathery plate body

• Attached to the substratum like a root-like stalk

• Shallow marine water

Oscula

(Carteriospongia)

Seen on the surface