Phylum PoriferaPhylum PoriferaThe “Pore Bearers”The “Pore Bearers”
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Phylum Porifera : The SpongesPhylum Porifera : The SpongesA few examplesA few examples
Yellow Tube SpongeStovepipe Sponges Red Volcano Sponge
Identifying Characteristics of the Identifying Characteristics of the members of Phylum Poriferamembers of Phylum Porifera
• Non-coelomates (therefore do not possess any true body systems although they do have highly specialized cells that perform many functions)
• Mostly asymmetric (some exhibit radial symmetry)
• Possess a GASTROVASCULAR CAVITY (GVC)
• Filter Feeders : through pores and special cells that line the GVC
• Posses a skeleton made up SPICULES composed of either calcium, silica or spongin
• Hermaphroditic : can reproduce sexually (do not self fertilize) or asexually by regeneration or budding
• Sessile (anchored to the ocean floor as an adult)
• Found mainly in marine habitats
Basic Structure of a SpongeBasic Structure of a Sponge
The Gastrovascular CavityThe Gastrovascular Cavity Has only one openingHas only one opening Serves two primary functionsServes two primary functions
1. “Gastro” 1. “Gastro” digests and absorbs food and nutrientsdigests and absorbs food and nutrients
2. “vascular”2. “vascular”serves as a primitive circulatory system as it serves as a primitive circulatory system as it moves moves
nutrients around to other parts of the bodynutrients around to other parts of the body
Basic Functions of the Internal CavityBasic Functions of the Internal Cavity1.1. To filter water as it To filter water as it
passes through the passes through the sponge for food and sponge for food and oxygen (see collar cell oxygen (see collar cell enlargement)enlargement)
2.2. To extract particles of To extract particles of food from passing food from passing water and digest food water and digest food either in collar cell food either in collar cell food vacuoles or by roaming vacuoles or by roaming amoeboid cells.amoeboid cells.
3.3. To get rid of waste To get rid of waste products through the products through the osculumosculum
Collar Cells at work bringing in water and retrieving oxygen and food for the sponge
Ecological Importance of SpongesEcological Importance of Sponges• Sponges provide Sponges provide
shelter and food for shelter and food for other ocean creaturesother ocean creatures
• Sponges can release Sponges can release chemicals that help to chemicals that help to break up old shellsbreak up old shells
• Because sponges are Because sponges are filter feeders they are filter feeders they are very sensitive to water very sensitive to water pollution as it will pollution as it will quickly clog their pores quickly clog their pores and destroy the and destroy the sponge. Therefore a sponge. Therefore a lack of sponges in a lack of sponges in a certain area is a good certain area is a good indication that there is indication that there is pollution in the area pollution in the area and more of the ocean and more of the ocean life is potentially at risklife is potentially at risk
Sea Crab living inside a Fluorescent sponge
Economical Importance of SpongesEconomical Importance of Sponges
• At one time there At one time there was a market for was a market for sponges to be used sponges to be used in the bathroom in the bathroom and the kitchen and the kitchen because of their because of their ability to absorb ability to absorb water, however water, however synthetic sponges synthetic sponges have replaced this have replaced this industryindustry
Sea sponge Skeleton to be used in the bathroom for washing
Super Cool Sponge FactsSuper Cool Sponge Facts• Each species of sponge Each species of sponge
somehow knows somehow knows exactly which day of the exactly which day of the year the other members year the other members of its species will of its species will release their gametes release their gametes into the water. This is into the water. This is how sponges are able how sponges are able to cross fertilize.to cross fertilize.
• The Loofah “Sponge” The Loofah “Sponge” sold in many stores is sold in many stores is not actually a sponge at not actually a sponge at all…. It’s the inside of a all…. It’s the inside of a plant known as a gourd!plant known as a gourd!
Purple Vase Sponge and a sea fan
Phylum CnidariaPhylum CnidariaCnidos = “Stinging Needle”Cnidos = “Stinging Needle”
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4 Classes of Phylum Cnidaria4 Classes of Phylum Cnidaria
HYDROZOA – Obelia, Hydra (above), Portuguese Man O War
SCHYPHOZOA - Jellyfish
ANTHOZOA – anemones (above), corals, sea fans
CUBOZOA – box jellies (sea wasps)
Identifying Characteristics of the members of Phylum Cnidaria
• Non-coelomates & therefore do not possess any true body systems or organs. 3 germ layers include ectoderm (protection), endoderm (inner lining) and mesoglea
• Exhibit radial symmetry• Possess tentacles used in transportation and for
capturing food and stinging cells called nematocysts.• Possess a Gastrovascular Cavity (GVC)• Primitive Nervous System (Nerve net)• Hermaphroditic : can reproduce sexually (do not self
fertilize) or asexually by regeneration or budding• Have a motile (medusa) and a sessile (polyp) stage in
their lives• Found in marine habitats
Gastrovascular Cavity (GVC)Gastrovascular Cavity (GVC)• The inner cavity responsible for digestion, The inner cavity responsible for digestion,
circulation, respiration and excretion.circulation, respiration and excretion.
• Disadvantages of having a GVC include: Disadvantages of having a GVC include: – There is only one opening….. The mouth is the anus…..There is only one opening….. The mouth is the anus…..
Tentacle
Tentacle Gastrovascular Cavity
Mouth and Anus
Calcified Shell (Coral)Note: This diagram shows the GVC in the polyp body type.
2 Body Types Present in Phylum Cnidaria2 Body Types Present in Phylum Cnidaria
1.1. PolypPolyp- Sessile (no movement Sessile (no movement
as they are anchored to as they are anchored to the ground))the ground))
- Tentacles face upTentacles face up- asexualasexual- Ex. Hydra, sea Ex. Hydra, sea
anemones, coralanemones, coral
2.2. MedusaMedusa- MotileMotile- Tentacles face downTentacles face down- sexualsexual- Ex. Jellyfish, sea waspsEx. Jellyfish, sea wasps
The stinging cells: NematocystsThe stinging cells: Nematocysts
• Nematocysts are most Nematocysts are most commonly located at commonly located at the end of tentaclesthe end of tentacles
• Are composed of Are composed of special cells called special cells called cnidocytes that cnidocytes that produce a toxinproduce a toxin
• When a trigger is When a trigger is stimulated it releases stimulated it releases a barbed needle that a barbed needle that penetrates the flesh penetrates the flesh and injects toxins. and injects toxins.
• Nematocysts are used Nematocysts are used to ward off predators to ward off predators or attack preyor attack prey
A discharged nematocyst
Life cycle of a typical JellyfishLife cycle of a typical Jellyfish
#1-10 exhibit the formation of the polyp life form.
#11 shows the polyp undergoing asexual reproduction in the form of budding. The top of the polyp breaks off and goes on to form the medusa stage of the jellyfish’s life. #12-14 shows the formation of the adult medusa
The medusa will then go on to produce and release egg and sperm into the water. The eggs will be cross fertilized by the sperm of another medusa and eventually develop into a new polyp
This alternating between two life forms is termed ALTERNATION OF GENERATIONS
Brooding Anemones
From a single anemone other polyps are forming which will eventually break off and settle on the ocean floor to form
new anemones. This is why many of the same type of anemone are often observed in the same area as the new
polyps are not capable of traveling far distances.
Ecological Importance of CnidariansEcological Importance of Cnidarians
• Filter and clean the waterFilter and clean the water• Form symbiotic Form symbiotic
relationships will other relationships will other ocean life ocean life – Examples. Examples.
• Clownfish and Clownfish and anemone anemone (remember Finding (remember Finding Nemo?)Nemo?)
• Coral will die as the Coral will die as the temperature of the water temperature of the water increases. Death of coral increases. Death of coral often precedes death of often precedes death of entire ecosystemsentire ecosystems
The clownfish are immune to the stinging cells of the clownfish anemone. Therefore the anemone provides protection and shelter for the clownfish and in turn the clownfish clean the anemone.
Super Cool Killer CnidariansSuper Cool Killer CnidariansThe Portuguese Man O’ War The Portuguese Man O’ War • Looks like a jellyfish but is Looks like a jellyfish but is
actually a colony of specialized actually a colony of specialized polyps and medusaspolyps and medusas
• The sting from their tentacles The sting from their tentacles causes excruciating pain and causes excruciating pain and sometimes deathsometimes death
• Named for its air bladder which Named for its air bladder which looks like the sails of a looks like the sails of a Portuguese fighting shipPortuguese fighting ship
Super cool fact: Loggerhead Super cool fact: Loggerhead turtles are actually immune to turtles are actually immune to their toxins and feed on the their toxins and feed on the Portuguese Man O’ WarPortuguese Man O’ War
Portuguese Man O’ War Physalia physalis
A common sign to observe near
Australian Beaches
Box JellyfishBox Jellyfish• Possess the most deadly Possess the most deadly
venom (toxins) in the venom (toxins) in the animal kingdom which animal kingdom which cause anaphylaxis shock cause anaphylaxis shock and deathand death
• In Nov. – April they are In Nov. – April they are abundant in Australian abundant in Australian waters but it is not known waters but it is not known where they go for the where they go for the winterwinter
• Through ultrasonic tagging Through ultrasonic tagging it has been found that they it has been found that they sleep on the ocean floor sleep on the ocean floor between 3pm and dawn to between 3pm and dawn to conserve energy and avoid conserve energy and avoid predatorspredators
• Possess 22 very simple Possess 22 very simple light sensing eyeslight sensing eyes
Box Jellyfish Chironex flecker
This jellyfish has had an ultrasonic tag attached (very carefully!) to it in order to help learn more about the migration patterns of these
cnidarians
JellyJelly FISH OUT OF WATERFISH OUT OF WATER