MARINE INVERTEBRATES: STOP 2 PHYLUM CNIDARIAN - JELLYFISH

JELLYFISH INTRO JELLYFISH INTRO

3 CLASSES SCYPHOZOA SCYPHOZOA COMMON JELLIES COMMON JELLIES HYDROZOA HYDROZOA PORTUGESE MAN-OF-WAR PORTUGESE MAN-OF-WAR OBELIA OBELIA CUBOZOA CUBOZOA BOX JELLIES BOX JELLIES

COMMON CHARACTERISTICS EVOLVED OVER 600 MILLION YEARS AGO EVOLVED OVER 600 MILLION YEARS AGO CONTAIN CNIDOCYTES – STINGING CELLS CONTAIN CNIDOCYTES – STINGING CELLS WHICH EXPEL BARB-LIKE NEMATOCYSTS WHICH EXPEL BARB-LIKE NEMATOCYSTS MOST BLIND MOST BLIND EXCEPT BOX JELLIES EXCEPT BOX JELLIES HAVE EYE CLUSTERS HAVE EYE CLUSTERS

COMMON CHARACTERISTICS ALL ARE CARNIVOROUS ALL ARE CARNIVOROUS SINGLE-OPENING DIGESTIVE TRACT (2 WAY) SINGLE-OPENING DIGESTIVE TRACT (2 WAY) MOUTH AND ANUS ARE AT SAME OPENING MOUTH AND ANUS ARE AT SAME OPENING ECTOTHERMIC ECTOTHERMIC NO BRAIN, SKELETAL OR CIRCULATORY SYSTEM NO BRAIN, SKELETAL OR CIRCULATORY SYSTEM

BODY PLAN VERY BASIC BODY PLAN VERY BASIC BODY PLAN RADIAL SYMMETRY RADIAL SYMMETRY ONLY TRUE ORGANS ARE GONADS ONLY TRUE ORGANS ARE GONADS

BODY PLAN 2 TISSUE LAYERS 2 TISSUE LAYERS ECTODERM – OUTER COVERING ECTODERM – OUTER COVERING ENDODERM – INNER LINING ENDODERM – INNER LINING CONNECTED TO EACH OTHER BY MESOGLEA CONNECTED TO EACH OTHER BY MESOGLEA NON-CELLULAR JELLYLIKE MATERIAL NON-CELLULAR JELLYLIKE MATERIAL

PHYSIOLOGY HAVE A NERVE NET AND BASIC RECEPTORS FOR IMPULSES TO MOVE HAVE A NERVE NET AND BASIC RECEPTORS FOR IMPULSES TO MOVE OXYGEN TAKEN IN DIRECTLY THROUGH TISSUES FROM WATER COLUMN OXYGEN TAKEN IN DIRECTLY THROUGH TISSUES FROM WATER COLUMN TENTACLES MAY BE METERS IN LENGTH & CARRY POISONS THAT CAUSE SEVERE PAIN OR DEATH

MOST DANGEROUS JELLYFISH MOST DANGEROUS JELLYFISH WHEN THESE STINGER CELLS ARE TRIGGERED THE INTERNAL PRESSURE BUILDS UP TO A MASSIVE 2,000 PSI (136 ATMOSPHERES) WHEREUPON IT BURSTS, FIRING OUT A TOXIN HARPOON THIS IS ONE OF THE FASTEST MOVEMENTS IN NATURE AND QUICKER THAN A BULLET.

LIFE CYCLE HAVE BOTH ASEXUAL POLYPS & SEXUAL MEDUSA STAGES IN THEIR LIFE CYCLES ADULT MEDUSA STAGE RELEASES EGGS & SPERM INTO WATER

LIFE CYCLE FERTILIZATION PRODUCES CILIATED PLANULA LARVA THAT SETTLES TO THE BOTTOM, ATTACHES, & FORMS TENTACLES NEW MEDUSA BUD OFF OF REPRODUCTIVE POLYPS & FORM ADULT JELLYFISH

LIFE CYCLE UNLIKE CORALS, SPEND MOST OF THEIR LIFE IN MEDUSA STAGE UNLIKE CORALS, SPEND MOST OF THEIR LIFE IN MEDUSA STAGE RANGE IN SIZE OF 2MM-30M LONG RANGE IN SIZE OF 2MM-30M LONG Jellies Corals

LIFE CYCLE MEDUSA FORMS ARE USUALLY FREE- SWIMMING BELL-SHAPED ANIMALS WITH TENTACLES THAT HANG DOWN AROUND THE MOUTH THICK LAYER OF MESOGLEA FOR SUPPORT

LION’S MANE JELLYFISH

PORTUGESE MAN OF WAR PORTUGESE MAN OF WAR