The group gets its name from the eight rows of fused cilia called comb plates that encircle the body. While some ctenophores have tentacles, they do not contain the stinging cells found in those of cnidarians.
Home Zoo-lab. Class Hexactinellida - Euplectella Venus' flower basket — a leucon sponge Class Demospongiae - larger marine sponges, including commercial and bath sponges as well freshwater sponges such as Spongilla that produces gemmules; all leucon type.
Phylum Ctenophora - comb jellies. Introduction to the Sponges The Phylum Porifera "pore bearers" contains approximately 5, species of animals called sponges. Phylum Porifera - Class Calcarea Lab-4 01 Class Calcarea contains sponges with calcium carbonate spicules of three or four rays. Phylum Porifera - Class Hexactinellida Lab-4 02 Sponges in the Class Hexactinellida are commonly called glass sponges because their six-rayed spicules are made silica.
Phylum Porifera - Class Demospongiae Lab-4 04 In addition to many marine forms, the Class Demospongiae also contains about species of freshwater sponges.
Introduction to the Cnidarians The Phylum Cnidaria contains about 9, species of hydras, jellyfishes, sea anemones, sea fans, sea pens, corals, etc. Gonionemus Lab-4 05 Gonionemus is a marine hydrozoan jellyfish that swims with its convex aboral surface directed upward and its concave oral surface facing downward.
Obelia Lab-4 06 Obelia is a colonial, marine hydrozoan that contains both feeding polyps called hydranths and reproductive polyps called gonangia. Physalia Lab-4 07 Physalia the Portuguese man-o-war consists of a floating colony of different kinds of individuals attached to a gas-filled float called a pneumatophore. Hydra Lab-4 08 Hydra is a genus of simple freshwater animals possessing radial symmetry.
Craspedacusta Lab-4 09 These tiny hydrozoan jellyfish have been found in calm waters of freshwater lakes, ponds, reservoirs and large rivers on all continents. Phylum Cnidaria - Class Scyphozoa Lab-4 10 In the true jellyfishes most of which are found floating in the open ocean the medusa is the dominant form, and the mesoglea which is thick contains cells as well as fibers.
Phylum Cnidaria - Class Anthozoa The anthozoans "flower animals" include about 6, species of sea anemones , corals , sea fans , etc. Phylum Ctenophora Lab-4 14 This small phylum contains about 90 species of marine organisms called comb jellies, all of which have biradial symmetry. Leucosolenia w. Lab-4 15 This is a slide of a simple marine sponge called Leucosolenia.
Grantia Scypha c. Lab-4 16 Incurrent canal Radial canal Spongocoel This slide shows a cross section through the body of calcareous marine sponge called Grantia also called Scypha in some books. Sponge gemmule Lab-4 19 This slide shows an internally-produced, asexual bud that is called a gemmule. Hydra c. Lab-4 20 Epidermis Gastrodermis Mesoglea Gastrovascular cavity This slide shows a cross section through the body of Hydra, a small freshwater cnidarian.
Hydra budding Lab-4 22 Hypostome Tentacles Epidermis. Obelia w. Lab-4 23 Hydranths Gonangia This is a slide of many stained specimens of Obelia, a colonial marine cnidarian that shows a distinct polymorphism in the organization of its members. Obelia medusa w. Lab-4 26 This slide shows a medusa from the colonial cnidarian Obelia. Metridium w. Lab-4 27 This slide shows a cross section through the pharyngeal region of the sea anemone Metridium, an anthozoan cnidarian.
Close-Up of the Pharynx Lab-4 28 Siphonoglyph Retractor muscle Primary septum Pharynx Gastrovascular cavity This slide shows a magnified view of a cross section through the pharynx of the sea anemone Metridium. Close-Up of the Septa Lab-4 29 Primary septum Secondary septum Tertiary septum Retractor muscle Septal filament Gastrovascular cavity This slide shows a magnified view of a cross section through the body wall of the sea anemone Metridium.
Close-Up of the Body Wall Lab-4 30 Epidermis Mesoglea Gastrodermis Septal filament Primary septum Secondary septum This slide shows a magnified view of a cross section through the body wall of the sea anemone Metridium. Hydra nematocyst Lab-4 31 This slide shows two discharged nematocysts from Hydra, a small freshwater cnidarian.
Aurelia planula Lab-4 32 This slide shows the ciliated planula larva that results from the union of egg and sperm from the scyphozoan jellyfish Aurelia. Aurelia scyphistoma Lab-4 33 This slide shows the polyp stage of development of the jellyfish Aurelia called a scyphistoma. Aurelia early strobila Lab-4 34 This slide shows the early strobila stage of the jellyfish Aurelia. Aurelia late strobila Lab-4 35 This slide shows the late strobila stage of the jellyfish Aurelia. Aurelia ephyra Lab-4 36 This slide shows an ephyra, which is the last stage of the complex life cycle of the jellyfish Aurelia.
Gonionemus bioplastic mount Lab-4 37 1. Manubrium Gonads Tentacles Radial canal Circular ring canal Statocyst This slide shows a stained specimen of the small marine hydrozoan jellyfish Gonionemus that has been embedded in a Lucite block. The adult medusa normally swims with its convex surface directed upward and its concave surface downward. Extending downward from the center of bell is the manubrium with a mouth at its tip. The conspicuous gonads can be seen attached to the four radial canals that extend from the manubrium to the circular canal at the margin of the bell.
Hollow tentacles that connect with the circular canal are equipped with numerous batteries of stinging nematocysts as well as adhesive pads that aid in holding on to captured prey. Between the bases of the tentacles are structures called statocysts that serve as balancing organs. Around the inner margin of the bell is a thin, circular flap of tissue called the velum, which is believed to aid in swimming. Scyphozoan jellyfish lack a velum and are usually larger than hydrozoan forms.
Aurelia bioplastic mount Lab-4 38 Oral arm Ring canal Radial canals Gastric pouch Gonad Rhopalium This slide shows a small stained specimen of the moon jellyfish Aurelia that has been embedded in a Lucite block.
These common and widely distributed marine jellyfish can reach a size of 30 centimeters. Note the four oral arms that extend from a central mouth. Along these arms are many short oral tentacles that help to capture small food items. After passing through the mouth, food enters a gastrovascular cavity that is divided internally into four gastric pouches. Within the gastric pouches are the horseshoe-shaped gonads as well as a ring of gastric filaments containing nematocysts that kill or immobilize any food items still active.
Numerous branching radial canals connect to an outer circular canal that runs around the margin of the bell. Small indentations around the margin of this bell contain sense organs called rhopalia. Comb jelly bioplastic mount Lab-4 39 This slide shows a stained specimen of the comb jelly Pleurobrachia that has been embedded in a Lucite block. Sponge model Lab-4 40 Ostium opening into an incurrent canal Radial canal Apopyle Spongocoel Osculum Bud This image shows model of a typical sycon sponge.
In syconoid sponges, water enters incurrent canals shown in blue on the model through dermal pores called ostia. From there, the water passes through internal pores called prosopyles not visible on the model into radial canals shown in yellow on the model. These radial canals are lined with flagellated choanocytes. From the radial canals, water passes through internal pores called an apopyles into the central spongocoel to exit through a large opening called the osculum.
All sponges are capable of both sexual and asexual reproduction. One form of asexual reproduction is the formation of external buds 6 that can detach or remain to form colonies. Freshwater sponges produces internal buds called gemmules at the onset of unfavorable conditions such as the drying out or freezing of the aquatic habitats in which they live.
Although the parental sponge may die and disintegrate, these structures are highly resistant to adverse conditions and will develop into new sponges when conditions improve. How do sponges get their nutrition?
Sponges are filter feeders and retrieve their nutrition from filtering the water that enters their pores and exits their osculum. The food is captured by choanocytes and also amoebocytes who can digest it. Amoebocytes can also digest the food and carry nutrients to other cells. Sponges use direct diffusion to exchange gases. The gases diffuse through the surface of the sponge. Once inside, they diffuse to individual cells.
Waste products are expelled through the osculum by the current created by the choanocytes to pull water into the sponge. Sponges have no distinct respiratory system because they are so primitive, but they do require oxygen to survive like any other organism.
The small pores also known as ostia in the sponge allow the sponge to absorb oxygenated water to receive the oxygen it needs. Spicules are structural elements found in most sponges. They provide structural support and deter predators. Large spicules that are visible to the naked eye are referred to as megascleres, while smaller, microscopic ones are termed microscleres.
There are about to 10, of species of Porifera that are known today. Out of them only species live in fresh water. The rest of the sponges dwell in salt-water. Sponges are very primitive creatures that evolved around million years ago 1. Water enters the spongocoel through hundreds of tiny pores Ostia and exits through the larger opening osculum. Asconoid Type: Asconoid type is present in these sponges whose body is vase-like and radially symmetrical.
The wall is extremely thin. It encloses a large spongocoel atrium opening at the summit by a narrow osculum. The spongocoel is lined by choanocytes. There are three classes within the phylum porifera: Calcerea, Desmospongia, and Hexactinellida. Sponges are divided into these classes based primarily on the composition of their spicules and skeletal fibers. Spicules are rod-shaped cellular projections that make up the skeleton of sponges.
How Do Sponges Protect Themselves? In sexual reproduction, they may play either role. After fertilization in the sponge, a larva is released into the water.
It floats around for a few days and then sticks to a solid to begin its growth into an adult sponge. Sponges are also able to reproduce asexually through budding. This is when a small piece of sponge is broken off but is still able to survive and grow into another sponge. Sponges are also able to repair damages to their bodies. These characteristics of sponges are ideal because even small parts of sponges may survive in the water. Diversity is created when different sponges reproduce with other different sponges.
Campbell, Neil A. David, Seonaid. Class Notes - Lab Manual. Correspondence regarding this page should be directed to , Havergal College. Treehouses are authored by students, teachers, science enthusiasts, or professional scientists. Anyone can sign up as a treehouse contributor and share their knowledge and enthusiasm about organisms. Treehouse contributions are checked for general accuracy and quality by teachers and ToL editors, but they are not usually reviewed by expert scientists.
If you spot an error, please get in touch with the author or the teacher. This page is a treehouse that is attached to a branch of the Tree of Life. For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.
All rights reserved. Investigation All About Sponges spongejk1 The scientific name of a sponge is Porifera, which means pore-bearing. Information on the Internet Phylum Porifera description, structure, reproduction, body type, habitat The Secret Lives of Sponges - Solving Mysteries on a Coral Reef importance to ecosystem Sponge - Wikipedia, the free encyclopedia description, structure, reproduction, body type, taxonomy, pictures Sponges description, structure, type, reproduction Sponges - Phylum Poriphora description, structure, feeding, diagrams Introduction to Porifera structure, type, taxonomy, phylogeny.
References 1. Columbia Encyclopedia. Comments Our treehouse is designed to teach you about sponges. Through reading our treehouse, you will know the description and important characteristics of sponges. You will also learn about the structure of a sponge, with the help of a diagram, the habitat of sponges, and their importance to the ecosystem.
You will discover some interesting adaptations to the environment that sponges have.
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