Introduction: In our group, our task was to observe the selected four invertebrates and familiarize ourselves with their taxonomic levels through the organism’s mechanisms of feeding, motility, and reproduction. Our group used the prior knowledge we possessed about the Hydra, Rotifer, Gammas, and Planarian organisms to complete the lab. We knew that all of these small invertebrates have a freshwater habitat. Each organism differs in taxonomic levels from Genus to Species.
We knew that the Hydra reproduces with one of two methods: 1) by “budding” which is an asexual method of reproduction and 2) by reproducing through a sexual sperm and egg process. We also knew that the Rotifer was a round worm with a split tail. We had to find the “Jaws” of the invertebrate, in other words, a transparent, clear mascot that intakes food. Additionally, our group knew that the Gammas possesses a heart, an exoskeleton, and a digestive tract (outlined in yellow). Lastly, we knew that the Planarian is a flat arm that reproduces sexually and has an “celli” which responds to light.
Methods: 1 . Set up the lap table with four microscopes all with the magnification at xx. 2. Gather three flat slides, one depression slide and four slip covers. 3. Using a pipette, take a sample of Planarian and place the sample on one of the flat slides. 4. Take a slip cover and place it over the sample Just placed on the flat slide. Repeat two more times with the sample of Gammas and Rotifer. 5. Using a pipette, take a sample of Hydra and place it on the depression slide. 6. Place a slip cover over the sample of Hydra. . Carefully observe the four individual samples under the basic magnification. 8. Gradually move up in magnification level if a closer look at the sample is needed. 9. Draw and label what can be seen under the microscope onto the laboratory sketch pages. Repeat four times or until every sample has been studied. 10. Rinse off slides and return them to the front table. 11. Turn off the microscopes and return them under the lab table. Materials: Pipette Microscopes Depression Slides Flat Slides Slip Covers Sample of Planarian
Sample of Hydra Sample of Gammas Sample of Rotifer Discussion Questions: Planarian: Planarians or flat worms are classified under the Animal kingdom and are commonly known as Disguise tsarina. Planarians mechanism for travel is dependent upon the cilia surrounding the edge of its body. The cilia help to move the planarian in a gliding motion along any surface. Planarian feed on small invertebrates in their ecosystem as well as decaying organisms. Depending on the food ingested, the planarian will vary in size and length.
When it comes to digestion, Planarian digest their DOD using their pharynx. The pharynx, which is a long muscular tube, finds the food and sucks up the animal tissues to digest. Once in the system, digestion begins to take place. Planarian are primarily located in fresh or salt water, however a few may live in wet lands or under rocks and leaves. In terms of reproduction, planarians can reproduce sexually and asexually. In order to reproduce asexually, planarian split into two separate halves through a process of pinching, sometimes called fragmentation.
Each half will eventually turn into a flat worm. Sexual reproduction occurs when one planarian fertilizes the egg of another planarian with its sperm to create another planarian. Hydra: The Hydra, also known as the Hydra focus, can be found among submerged shoreline vegetation in unpolluted ponds and other quiet waters. When it comes to feeding, Hydra mainly feed on small aquatic invertebrates. In order to obtain and eat their food, the Hydra extends their body to its full length and then extends their tentacles. The tentacles slowly move around as they wait for contact with their prey.
When the entangles make contact they coil around the prey and within a couple of minutes the tentacles will surround the prey and begin to eat. When it comes to motion the Hydra is generally a sedentary or sessile animal, but they do readily move when hunting. The Hydra move by bending over and attaching themselves to some surface with their mouth and tentacles while at the same time releasing the foot, which is what the Hydra mainly uses when attaching to a surface. The Hydra moves in a “somersaulting” motion which allows them to move several inches in a day.
There are wow ways a Hydra can reproduce and that is either asexually or sexually. The asexual reproduction mentor Is also called Dually Ana tons Is winner ten Hydra produce buds in the body wall, which will eventually grow into mint-adult Hydra and break away when they are mature enough. During sexual reproduction the testes of the Hydra will release free-swimming sperm into the water, which can fertilize the eggs in the ovary of another Hydra. Gammas: Gammas or Gammas dubbed, is a crustacean in the family Cambridge. Most Gammas are scavengers or detersives.
They eat the leftovers of other species. Each Gammas has a segmented body with Jointed legs and a hard ex.-skeleton covering its body. While searching for food, Gammas Jump around in order to find the food they want to capture. They range in size from 1 to 340 millimeters (0. 039 to 13 in) and move very fast. The reproduction method for Gammas is sexual reproduction. Mature females hold their eggs while they are fertilized and until the young are ready to hatch. As a female ages, she produces more eggs in each brood. Mortality is around 25%-50% for the eggs.
There are no larval stages; the eggs hatch directly into a Juvenile form. Gammas is found in large numbers in dark banks of permanent water among submerged vegetation. They can also be found along bank weeds and other developing vegetation in springs and small streams. In addition, Gammas can also live on the beach, where it lives under decaying vegetation and stones. Aquatic Gammas is often whitish but is seen in other colors also. The color of terrestrial species varies from pale brown to greenish to brownish black when alive, but they often turn red when they die.