Porifera - Sponges Cnidaria: Jellyfish Annelida - Earthworms Mollusca - Squid Arthropoda - Grasshopper
porifera medusozoa lumbricana teuthida caelifera
Porifera (Sea Sponge) :
Sponges are large and their asymmetrical shape provides protection for marine animals like shrimps, sea stars, sea cucumbers, and snails. Sponges also have mutually beneficial relationships with bacteria, algae, and other plant-like protists; sponges attach to the sea floor, with spicules that act like a magnifying glass by focusing incoming life. This allows those plants to thrive, and they are then eaten by the marine animals housed by the sponge. The oxygen and nutrients that the plants create are very important to the sponge, which filters it out of the water and uses it to for energy.
Cnidaria (Jellyfish) : Jellyfish have specialized cells, unlike sponges. They have sensory cells - such as the oceli and statocysts - and also have a nerve net that allows them to detect stimuli. They also have digestive tissues like the gastrovascular cavity and the gastroderm. Jellyfish also have gonads and a mouth that aids with digestion in the gastrovascular cavity; they are also capable of some movement, and are not stable or fixed like the sponge. Jellyfish have radial symmetry, a mouth, and stages in its life. They are carnivorous, unlike the sponge.
Annelida (Earthworm): Cnidarians have specialized cells called statocytes, epidermal cells, and cells lining the gastrovascular cavity that helps digestion. Although the jellyfish has a more complex digestive mechanism than the filter-feeding sponges, worms have a closed digestive tract that has two separate openings. Worms have specialized cells that make up the sex organs (clitellum and seminal vesicle), heart, and the digestive intestine and track. They also have specialized cells that make up their circulatory system and brain. They have all of the following organs: pharynx, esophagus, seminal receptacle and vesicle, heart, crop, gizzard, intestine, dorsal vessel, ventral vessel, and small ring vessels. The worm’s overall body plan involves a segmented, bilaterally symmetrical plan, with a one-way digestive track that goes from the posterior end to the anterior end, which is unlike the cnidarians who contain radial symmetry, a central gastrovascular cavity, and are hydrostatic. Annelids also have a dorsal side, which has evolved to become a darker color in order to camouflage with surrounding dirt. The ventral side is lighter, and has setae, which help it grip and move in the dirt. Each segment is separated by a septum. Unlike the sponges, both the cnidaria and annelids have control of their movement.
Mollusca (Squid): The squid is more complex than the sponge, jellyfish, and worm. It has specialized sensory cells and structural cells that form complex organs not found in the previous phylums. Squids have mottled pigment cells called chromatophores that give it the ability to change color and camouflage with their environment. Several of the organs and complex structures include: branchial hearts, systemic heart, ovaries, testicles, seminal vesicles, pancreas, liver, kidney, brain, mantle shell, gills, ink sac. It also has a centralized nervous system and has cephalization. Unlike porifera, cnidaria, and worms, squids have separate sexes.
Arthropods (Grasshopper) : They have the ocelli, which is a sensory organ that detects light. They have specialized internal organs such as ones used for respiration, unlike the previous phylums grasshoppers have a network of branching tracheal tubes that extend through the body. They also have specialized malpighian tubules that extract waste from the blood and add them to feces. They also have a specialized exoskeleton made of chiton. Like the annelida, the grasshopper has segments, but is more complex because it has appendages that are specialized. These appendages include the antenna, claws, walking legs, jumping legs, wings, mouthparts, and aquatic animals can have flippers. The grasshopper has three distinct segments, the head, the thorax, and the abdomen. More modern nervous system that have two nerves that encircle the esophagus and connect the brain to a ventral nerve cord. Ganglia,, or groups of nerve cells, coordinate the movement of individual legs and wings to help the animal move efficiently.
Reflection:
I really enjoyed this unit. I've always enjoyed dissections, so getting to dissect a lot of species within a couple weeks was exciting. I learned a lot about each phylum through the research that we did before and after examining each species. For example, I was able to see that every animal had some type of symmetry -- whether radial or bilateral -- and different kinds of feeding mechanisms. By looking more closely at blood vessels, I was able to see which species had more centralized and advanced circulatory and nervous systems. It's amazing to see how each progressive phylum has such seemingly small differences that make it a completely different thing to study. My group was also really efficient and collaborated well; we split up jobs equally and rotated, so everyone had a chance to dissect as well as write up paragraphs, tables, and drawings.
porifera medusozoa lumbricana teuthida caelifera
Porifera (Sea Sponge) :
Sponges are large and their asymmetrical shape provides protection for marine animals like shrimps, sea stars, sea cucumbers, and snails. Sponges also have mutually beneficial relationships with bacteria, algae, and other plant-like protists; sponges attach to the sea floor, with spicules that act like a magnifying glass by focusing incoming life. This allows those plants to thrive, and they are then eaten by the marine animals housed by the sponge. The oxygen and nutrients that the plants create are very important to the sponge, which filters it out of the water and uses it to for energy.
Cnidaria (Jellyfish) : Jellyfish have specialized cells, unlike sponges. They have sensory cells - such as the oceli and statocysts - and also have a nerve net that allows them to detect stimuli. They also have digestive tissues like the gastrovascular cavity and the gastroderm. Jellyfish also have gonads and a mouth that aids with digestion in the gastrovascular cavity; they are also capable of some movement, and are not stable or fixed like the sponge. Jellyfish have radial symmetry, a mouth, and stages in its life. They are carnivorous, unlike the sponge.
Annelida (Earthworm): Cnidarians have specialized cells called statocytes, epidermal cells, and cells lining the gastrovascular cavity that helps digestion. Although the jellyfish has a more complex digestive mechanism than the filter-feeding sponges, worms have a closed digestive tract that has two separate openings. Worms have specialized cells that make up the sex organs (clitellum and seminal vesicle), heart, and the digestive intestine and track. They also have specialized cells that make up their circulatory system and brain. They have all of the following organs: pharynx, esophagus, seminal receptacle and vesicle, heart, crop, gizzard, intestine, dorsal vessel, ventral vessel, and small ring vessels. The worm’s overall body plan involves a segmented, bilaterally symmetrical plan, with a one-way digestive track that goes from the posterior end to the anterior end, which is unlike the cnidarians who contain radial symmetry, a central gastrovascular cavity, and are hydrostatic. Annelids also have a dorsal side, which has evolved to become a darker color in order to camouflage with surrounding dirt. The ventral side is lighter, and has setae, which help it grip and move in the dirt. Each segment is separated by a septum. Unlike the sponges, both the cnidaria and annelids have control of their movement.
Mollusca (Squid): The squid is more complex than the sponge, jellyfish, and worm. It has specialized sensory cells and structural cells that form complex organs not found in the previous phylums. Squids have mottled pigment cells called chromatophores that give it the ability to change color and camouflage with their environment. Several of the organs and complex structures include: branchial hearts, systemic heart, ovaries, testicles, seminal vesicles, pancreas, liver, kidney, brain, mantle shell, gills, ink sac. It also has a centralized nervous system and has cephalization. Unlike porifera, cnidaria, and worms, squids have separate sexes.
Arthropods (Grasshopper) : They have the ocelli, which is a sensory organ that detects light. They have specialized internal organs such as ones used for respiration, unlike the previous phylums grasshoppers have a network of branching tracheal tubes that extend through the body. They also have specialized malpighian tubules that extract waste from the blood and add them to feces. They also have a specialized exoskeleton made of chiton. Like the annelida, the grasshopper has segments, but is more complex because it has appendages that are specialized. These appendages include the antenna, claws, walking legs, jumping legs, wings, mouthparts, and aquatic animals can have flippers. The grasshopper has three distinct segments, the head, the thorax, and the abdomen. More modern nervous system that have two nerves that encircle the esophagus and connect the brain to a ventral nerve cord. Ganglia,, or groups of nerve cells, coordinate the movement of individual legs and wings to help the animal move efficiently.
Reflection:
I really enjoyed this unit. I've always enjoyed dissections, so getting to dissect a lot of species within a couple weeks was exciting. I learned a lot about each phylum through the research that we did before and after examining each species. For example, I was able to see that every animal had some type of symmetry -- whether radial or bilateral -- and different kinds of feeding mechanisms. By looking more closely at blood vessels, I was able to see which species had more centralized and advanced circulatory and nervous systems. It's amazing to see how each progressive phylum has such seemingly small differences that make it a completely different thing to study. My group was also really efficient and collaborated well; we split up jobs equally and rotated, so everyone had a chance to dissect as well as write up paragraphs, tables, and drawings.