Phylum Nematoda, (example, roundworm)
This Phylum is a diverse one with many organisms living in different environments. There are about 25000 different animals within this group and more than half are parasitic. The one that we looked into and dissected was the Round Worm. There are certain requirements for a living thing to actually be classified as "living". There are 6 requirements that need to be met. The first is, "is the thing composed of cells?". In the case of the round worm, in the epidermis there is a single layer of cells, underneath the epidermis is the muscle cells and they also have nerve cells that are supported with the nervous system. The second expectation is "Living things are in levels of organization". Round worms have a Nervous System, Excretory system, and a digestive system all containing different specialized cells allowing for the animal to live. The third requirement is "living things require energy". Round worms, like humans, use food as there source of energy. They consume mucus, intestinal lining, bacteria and fungus. The 4th requirement is "living things respond to their environment". Round worms do this with sensory organs. They have sensory hairs and papillae which give the worm a sense of touch. Round worms do have brains which allow the worm to sense danger and go towards food. The 5th requirement is that "living things grow". Round worms can grow from feeding on other things such as bacteria and fungus and mucus. The 6th living thing is that "living things reproduce". Round worms mate with other female roundworms by fertilizing there sperm and the egg.
Evolution: They have evolved to have an unidirectional digestive system. Food is taken from the mouth, processed in a long tube where nutrients are absorbed into tissues.
Dissection: The dissection for this roundworm in all honesty was my least favourite as it was the least interesting. But even then a learning experience came from it and that was to see how these little parasites can work. The insides of the roundworm were laced with its long intestine tubes which we had to move in order to see the actual organs that the worm possesses. It also smelt pretty gross :/
Phylum Annelida, (Example, Earthworm)
This phylum consists of organisms such as earthworms, segmented worms, leeches and lug worms. These are found at moist terrestrial environments. There are over 2000 species in this phylum. The Annelid that we studied was an earthworm. The earthworm can be classified as a living thing because it fits all the requirements of a living thing. The earthworm is composed of cells just like every other living thing. We know this because if the organism didn't have cells then the whole animal would not be able to function and things such as the digestive system would not be effective as cells and other substances are secreted. The earthworm is classified in different levels of organisation as just like roundworms, they have a nervous system, digestive system and a excretory system. Earthworms require energy in the form of food also like the roundworms. They eat soil that includes dead remains of organisms and nutrients that lay in the ground. Earthworms respond to their environment by sensory organs much like the roundworms, which identify different vibrations, light and danger. Earthworms also grow from the nutrients that they eat from the soil. The segments that make up the worm can become larger and larger with more intake of food to contain all that they eat. Earthworms reproduce by a different method of dividing it self into to and they then reproduce to make identical offspring and this process is call meiosis.
Evolution: Have evolved from the ocean to live on land where the feeding for the worm is greater and this allows them to live longer and pass genes on to the next generation.
Dissection: Was not present for the dissection. However I did take some notes from other blogs on what the dissection was like.
- Had a long tube where most or all the organs were located around
-food that was undigested was still inside the worm
Phylum Arthropod (example, Grasshoppers)
Description on Phylum: Arthropod have an exoskeleton and joint appendages in their visual appearance. These animals in this phylum have been adapted to live in almost any type of environment and are very suitable for doing so. They range greatly in size from plankton to large crabs
Feeding: The Grasshopper is a herbivore, meaning that it only eats plants and vegetation rather than meat like other animals. They feed on farmers crops which is a big negative for farmers who are trying to make a living.
Respiration: Breathe through holes called spiracles that are hidden behind the wings of the Grasshopper. The air enters the holes through the front and exits from the back.
Reproduction: Grasshoppers reproduce sexually through meiosis. The female lays about 10-25 eggs on a layer of foam she secretes. The offspring will shed 5-6 times after being born and then will wander into the environment and continue the cycle.
Digestive system: Grasshoppers break down food in different phases. Firstly, the food goes into the foregut where saliva breaks it down, and then it gets passed on to the mid gut where a digestive juice called caecae does absorption to get the food out.
Nervous System: controlled by Ganglia, which is a loose group of nerve cells.
Evolution: the Grass hopper has evolved tremendously and is a species that is well adapted for humans to study and learn how evolution works. Grasshopper are prey for many predators in the wild and over years the slower and ones that cannot fly would be eaten and not pass on their genes. Therefore, the ones that could fly and that would jump higher and faster would survive and pass on their genes to the future grasshoppers.
The dissection: was very tough at time to crack through the hard surface of the skin that the grasshopper possesses. We first found out if the animal was female or male by looking if it had a digger at the back, which is used by females to dig into the soil to lay their eggs.
Phylum Echinodermata, (example, Starfish)
Description: Marine animals. Adults have radial symmetry and are found at every ocean depth.
Feeding: The starfish can turn its stomach inside out and lay it self on its prey, crushing it and taking out all the juices it needs.
Reproduction: Both sexually and asexually. Special species can reproduce broken parts of itself which is basically asexual reproduction.
Breathing: Contain Papulae which are circular dots around the starfish which allow oxygen from water and also tube feet that serve the same purpose.
Digestive System: In the pyloric stomach digestive enzymes are secreted to help in the absorption of nutrients. A starfish's diet includes small fishes, clams, and algae.
Nervous System: The central nervous system of a starfish consists of a radial nerve running the length of each ray.
- There is nerve rings that connect the radial nerves.
- Most of the senses go straight to the radial nerves as that is where the Star fish is centrally controlled.
Evolution: Unfortunately for humans, star fish disintegrate into the ocean bed once they die, therefore not leaving clear evidence for the evolution of the star fish and to see which species of it has evolved to survive in the ocean. This is something common with a lot of the species within this phylum.
Dissection: Was not present when we did this dissection so I watched a video on it and also looked at other blogs to see what it was like for my own personal gain of knowledge.
My classmates found the star fish to be very squishy, and a lot of "mush" on the inside. The outer layer was said to contain small dots which I learned were for breathing.
Phylum Vertebrata, (example, Grass Frog)
Description: All the animals in this phylum have backbones. Range in size from little frogs like the grass frogs, to the largest whale in the ocean, the blue whale. They make up 4% of all species in the world.
Feeding: When the frog is young, (tadpole), it only eats algae and other small plants. As the frog gets bigger and the digestive system demands more food, it becomes only a carnivore feeding on flies and other small insects by using its tongue to grasp its prey.
Circulation: Frogs have three-chambered hearts. Oxygenated blood from the lungs and de-oxygenated blood from the respiring tissues come into the heart and are separated by atriums. The aorta takes in oxygenated blood and the pulmonary artery for the de-oxygenated blood. There are special barriers just like in humans that prevent the back flow of blood and so the 2 types do not mix
Reproduction: Frogs are the type of species where the female lays eggs on a slimy layer in the water and the male frog comes and fertilizes them.
Respiration: Breathe through lungs. Absorb water through skin when underwater, allowing them to breathe underwater.
Digestive System: Use digestive enzymes in stomach and then food moves on to small intestine and large intestine to be excreted.
Nervous System: Has brain, spinal cord and many sensory nerves. It resembles the human brain in a way because of the high amount of complexity that is involved.
Evolution: Frogs were once sea mammals that only swam and acquired food in water. Over time, the frog has evolved to find food on land as there was not enough in the sea. They evolved to grow feet and legs to attain food and these frogs obviously would go on to live healthier and longer, passing on their genes to the next generation.
Dissection (THE CLICHE THING TO DO EH?): I was unfortunately not present for this dissection as it was said to be on of the fan favs according to my classmates. What surprised me when I saw picture of this dissection was how similar our insides are to the frog! It is almost scary to think that everything that is inside the frog is a minified version of what is inside of us. Crazy!
This Phylum is a diverse one with many organisms living in different environments. There are about 25000 different animals within this group and more than half are parasitic. The one that we looked into and dissected was the Round Worm. There are certain requirements for a living thing to actually be classified as "living". There are 6 requirements that need to be met. The first is, "is the thing composed of cells?". In the case of the round worm, in the epidermis there is a single layer of cells, underneath the epidermis is the muscle cells and they also have nerve cells that are supported with the nervous system. The second expectation is "Living things are in levels of organization". Round worms have a Nervous System, Excretory system, and a digestive system all containing different specialized cells allowing for the animal to live. The third requirement is "living things require energy". Round worms, like humans, use food as there source of energy. They consume mucus, intestinal lining, bacteria and fungus. The 4th requirement is "living things respond to their environment". Round worms do this with sensory organs. They have sensory hairs and papillae which give the worm a sense of touch. Round worms do have brains which allow the worm to sense danger and go towards food. The 5th requirement is that "living things grow". Round worms can grow from feeding on other things such as bacteria and fungus and mucus. The 6th living thing is that "living things reproduce". Round worms mate with other female roundworms by fertilizing there sperm and the egg.
Evolution: They have evolved to have an unidirectional digestive system. Food is taken from the mouth, processed in a long tube where nutrients are absorbed into tissues.
Dissection: The dissection for this roundworm in all honesty was my least favourite as it was the least interesting. But even then a learning experience came from it and that was to see how these little parasites can work. The insides of the roundworm were laced with its long intestine tubes which we had to move in order to see the actual organs that the worm possesses. It also smelt pretty gross :/
Phylum Annelida, (Example, Earthworm)
This phylum consists of organisms such as earthworms, segmented worms, leeches and lug worms. These are found at moist terrestrial environments. There are over 2000 species in this phylum. The Annelid that we studied was an earthworm. The earthworm can be classified as a living thing because it fits all the requirements of a living thing. The earthworm is composed of cells just like every other living thing. We know this because if the organism didn't have cells then the whole animal would not be able to function and things such as the digestive system would not be effective as cells and other substances are secreted. The earthworm is classified in different levels of organisation as just like roundworms, they have a nervous system, digestive system and a excretory system. Earthworms require energy in the form of food also like the roundworms. They eat soil that includes dead remains of organisms and nutrients that lay in the ground. Earthworms respond to their environment by sensory organs much like the roundworms, which identify different vibrations, light and danger. Earthworms also grow from the nutrients that they eat from the soil. The segments that make up the worm can become larger and larger with more intake of food to contain all that they eat. Earthworms reproduce by a different method of dividing it self into to and they then reproduce to make identical offspring and this process is call meiosis.
Evolution: Have evolved from the ocean to live on land where the feeding for the worm is greater and this allows them to live longer and pass genes on to the next generation.
Dissection: Was not present for the dissection. However I did take some notes from other blogs on what the dissection was like.
- Had a long tube where most or all the organs were located around
-food that was undigested was still inside the worm
Phylum Arthropod (example, Grasshoppers)
Description on Phylum: Arthropod have an exoskeleton and joint appendages in their visual appearance. These animals in this phylum have been adapted to live in almost any type of environment and are very suitable for doing so. They range greatly in size from plankton to large crabs
Feeding: The Grasshopper is a herbivore, meaning that it only eats plants and vegetation rather than meat like other animals. They feed on farmers crops which is a big negative for farmers who are trying to make a living.
Respiration: Breathe through holes called spiracles that are hidden behind the wings of the Grasshopper. The air enters the holes through the front and exits from the back.
Reproduction: Grasshoppers reproduce sexually through meiosis. The female lays about 10-25 eggs on a layer of foam she secretes. The offspring will shed 5-6 times after being born and then will wander into the environment and continue the cycle.
Digestive system: Grasshoppers break down food in different phases. Firstly, the food goes into the foregut where saliva breaks it down, and then it gets passed on to the mid gut where a digestive juice called caecae does absorption to get the food out.
Nervous System: controlled by Ganglia, which is a loose group of nerve cells.
Evolution: the Grass hopper has evolved tremendously and is a species that is well adapted for humans to study and learn how evolution works. Grasshopper are prey for many predators in the wild and over years the slower and ones that cannot fly would be eaten and not pass on their genes. Therefore, the ones that could fly and that would jump higher and faster would survive and pass on their genes to the future grasshoppers.
The dissection: was very tough at time to crack through the hard surface of the skin that the grasshopper possesses. We first found out if the animal was female or male by looking if it had a digger at the back, which is used by females to dig into the soil to lay their eggs.
Phylum Echinodermata, (example, Starfish)
Description: Marine animals. Adults have radial symmetry and are found at every ocean depth.
Feeding: The starfish can turn its stomach inside out and lay it self on its prey, crushing it and taking out all the juices it needs.
Reproduction: Both sexually and asexually. Special species can reproduce broken parts of itself which is basically asexual reproduction.
Breathing: Contain Papulae which are circular dots around the starfish which allow oxygen from water and also tube feet that serve the same purpose.
Digestive System: In the pyloric stomach digestive enzymes are secreted to help in the absorption of nutrients. A starfish's diet includes small fishes, clams, and algae.
Nervous System: The central nervous system of a starfish consists of a radial nerve running the length of each ray.
- There is nerve rings that connect the radial nerves.
- Most of the senses go straight to the radial nerves as that is where the Star fish is centrally controlled.
Evolution: Unfortunately for humans, star fish disintegrate into the ocean bed once they die, therefore not leaving clear evidence for the evolution of the star fish and to see which species of it has evolved to survive in the ocean. This is something common with a lot of the species within this phylum.
Dissection: Was not present when we did this dissection so I watched a video on it and also looked at other blogs to see what it was like for my own personal gain of knowledge.
My classmates found the star fish to be very squishy, and a lot of "mush" on the inside. The outer layer was said to contain small dots which I learned were for breathing.
Phylum Vertebrata, (example, Grass Frog)
Description: All the animals in this phylum have backbones. Range in size from little frogs like the grass frogs, to the largest whale in the ocean, the blue whale. They make up 4% of all species in the world.
Feeding: When the frog is young, (tadpole), it only eats algae and other small plants. As the frog gets bigger and the digestive system demands more food, it becomes only a carnivore feeding on flies and other small insects by using its tongue to grasp its prey.
Circulation: Frogs have three-chambered hearts. Oxygenated blood from the lungs and de-oxygenated blood from the respiring tissues come into the heart and are separated by atriums. The aorta takes in oxygenated blood and the pulmonary artery for the de-oxygenated blood. There are special barriers just like in humans that prevent the back flow of blood and so the 2 types do not mix
Reproduction: Frogs are the type of species where the female lays eggs on a slimy layer in the water and the male frog comes and fertilizes them.
Respiration: Breathe through lungs. Absorb water through skin when underwater, allowing them to breathe underwater.
Digestive System: Use digestive enzymes in stomach and then food moves on to small intestine and large intestine to be excreted.
Nervous System: Has brain, spinal cord and many sensory nerves. It resembles the human brain in a way because of the high amount of complexity that is involved.
Evolution: Frogs were once sea mammals that only swam and acquired food in water. Over time, the frog has evolved to find food on land as there was not enough in the sea. They evolved to grow feet and legs to attain food and these frogs obviously would go on to live healthier and longer, passing on their genes to the next generation.
Dissection (THE CLICHE THING TO DO EH?): I was unfortunately not present for this dissection as it was said to be on of the fan favs according to my classmates. What surprised me when I saw picture of this dissection was how similar our insides are to the frog! It is almost scary to think that everything that is inside the frog is a minified version of what is inside of us. Crazy!
Since I was not here for most of the dissections I did not have a chance to post about them before. What I did was that I basically just did my blog post about those dissections and integrated them into this post. Hope that helps understanding!
ReplyDeleteThis post was great - lots of good info and you integrated the dissections in well (even though you missed so many:().
ReplyDelete