Lab 36 Porifera and Cnidaria Phylum Porifera sponges

Lab 36 Porifera and Cnidaria

Phylum Porifera: sponges

Phylum Porifera: Simplest of Animals - Includes the sponges - Lack: symmetry, germ layers (tissues), gastrovascular cavity - Intracellular digestion -Body organized into a series of water canals and chambers: Osculum, pores and spongocoel

Sponges have cellular level of organization Types of cells: Choanocytes Amoebocytes Porocytes They are filter feeders Skeleton: Spongin fibers Spicules made of calcium carbonate or silica

Sketch • Spongin fibers (demo scope) • Spicules (demo scope)

Class Calcarea Calcium carbonate spicules in form of needles, or 3 -4 rayed stars Marine Includes: Grantia

Sketch each of the following: Preserved Grantia in a jar, use dissecting scope label osculum Grantia slide (group slide box) use dissecting scope Label osculum, spongiocoel

Class Hexactinellida Spicules are made of silica, in the form of 6 -rayed stars Marine, deep water Includes: Venus flower basket Sketch specimen (min 12)

Class Demospongiae Spicules are made of silica, but not 6 -rayed and/or spongin Marine and freshwater Includes: Bath sponges Sketch specimens

Medications from Sponges - 30%of all potential new natural medicines has been isolated in sponges. - About 75% of the recently registered and patented material to fight cancer comes from sponges.

Phylum Cnidaria Coral Sea Anemone Hydra Man-of-war Jellyfish

Cnidarians have two body forms - Symmetry: radial - Two body types: Free-swimming medusae or Sessile polyps - Diploblastic: ectodermis (ectoderm) and gastrodermis (endoderm) Mesoglea: extracellar matrix that lies between - Cnidarians have tissue level of organization

Phylum Cnidaria: Animals with stinging cells -All are aquatic and mostly marine -Predators - Equipped with specialized cells: cnidocytes contain a specialized stinging organelles: nematocysts

Cnidarian life cycle

Sketch each of the following: Obelia polyp (individual slide) dissecting scope label tentacles, mouth, reproductive polyp and feeding polyp Obelia medusa (group slide box) compound scope

Class Hydrozoa: Examples: Hydra (lacks medusa stage) Portuguese man-of-war (colonial polyps and there is a medusa stage too)

Sketch each of the following Hydra (live) dissecting scope Label tentacles and mouth Hydra budding (group slide) dissecting scope label tentacles and bud

Sketch each of the following: Portugese man of war (in jar) Label tentacles, polyps and bell

Class Scyphozoa: true jellyfish Example: Aurelia (moon jelly fish)

Sketch each of the following: Auerelia ephyra (group slide) Label mouth

Class Anthozoa: Examples: Stony corals Soft corals (sea fans) Sea Anemones

Sketch each of the following: Sea anemone (in jar) Basal disc, tentacles Stony coral skeleton Label a depression formed by a polyp Soft coral (sea fan)

Importance Some jellyfish are considered a delicacy Corals: Medicine cabinets for the 21 st century cancer cell inhibitor Sunscreen

End of chapter questions 2, 5, 7