Sequence | Background | Objectives | Materials | Activity | Extensions | Evaluations

TOPIC-TITLE Marine & Aquatic Resources Activities - Understanding the Process of Classification AUTHOR Roseann Pellegrino GRADE SUITABILITY Middle School SCOPE Biology Marine Biology

Sequence This lesson could be included in the marine sciences class when studying life in the water. Later discussions could encompass benthic classification. These lectures could follow a unit on how whales eat and what they prefer to eat. < < go top

Background Summary In marine and aquatic environments, several different food chains exist. These food chains are often interconnected, resulting in complex food webs. The base of all food chains begins with a producer. In the marine environment, the producers are phytoplankton. The next organisms in a food chain are the primary consumers, which are often different species of zooplankton. According to Greene (1998), zooplankton are animals and animal-like organisms that float and drift on the surface of the ocean. The term zooplankton refers to a great diversity of animal plankton, and therefore, zooplankton have been divided into two groups. The group referred to as meroplankton or temporary plankton is composed of larvae of fish, crabs, lobsters, oysters, clams, and other species of invertebrates. The larvae of these organisms remain at the surface only during the early part of their life cycles. As they grow and mature, these organisms will settle at the bottom and become part of the benthos or will swim in the nektonic level of the water column. The second group, holoplankton, is composed of the organisms that remain as part of the planktonic population their entire life cycles. < < go top Objectives Students will be able to do the following: Construct their own plankton net. Collect a sample of zooplankton. Classify and analyze the zooplankton sample. < < go top Materials Pantyhose One quart plastic soda bottle (cleaned) Wire hanger Wire cutters Rope Four collecting bottles with caps Labels Microscopes (compound and dissecting) Petri® dish Glass slide Medicine dropper "Crazy"® glue Thermometer Needle and thread Plastic tie wrap   < < go top Activity Construction of the plankton net: With the materials listed above, students working in pairs will carefully construct their own plankton nets. Carefully using a wire cutter, snip off the hook portion of a wire hanger. Bend the remaining part of the hanger into a circle and tape the ends of the wire together with electrical tape, covering the exposed ends. Cut one leg from a pair of pantyhose at the upper leg and snip off the toe so that you are left with a pantyhose tube. Save the other leg for later. Carefully cut two holes, one on each side of the one quart plastic bottle, approximately one-third of the way down from the bottle's mouth. Each hole should be 3 cm in diameter. Using the other leg of the pantyhose, cut two 4 cm x 4 cm squares of pantyhose. Using "Crazy"® glue, glue one 4 cm x 4 cm square piece of pantyhose to each hole in the bottle. Make sure the seams are glued completely and that there are no openings. Around the mouth of the bottle, place one end of the pantyhose tube you cut in the second procedure. Secure the pantyhose tube around the mouth of the bottle with a tie wrap, making sure it is very tight. Cut three pieces of rope, each measuring 30 cm in length, and tie each piece to the wire circle at equal distances away from each other. Tie the other ends together, making a bridle. Tie a 4 m piece of rope to that end. Using a needle and thread, sew the other end of the pantyhose tube around the wire circle so the tube is now open all the way down to the bottle. Hypothesis: Without having collected the plankton, predict the purpose of each part of the plankton net, in as much detail as possible. Take students to several different collecting locations. Students should collect their samples using their plankton nets and should pour each sample into an appropriately labeled collecting bottle with a cap. Students are to record the water's surface temperature at each location and tape to the collecting bottle. Students should also record, in a field notebook, observations of each location, including weather, physical composition of the sampling area, and surface conditions. Bring all samples back to the classroom for further study. In the lab notebook, students should describe and sketch individual organisms from each sample viewed under the microscope. Keep the descriptions/sketches for each location separate. Using these descriptions, group/classify the organisms observed. Compare each location's classification. After completing all location classifications, students should compare them to the actual scientific classifications you provide. Students should discuss the following questions: Regarding your own classification system, how did each location differ or how were they the same? Were there greater numbers of one type of organism in a particular location? Describe the other factors that might explain the variation of organisms in one location. Compare the similarities and differences between your classification system and the scientific classification system. What kinds of information might using a plankton net, observation, and classification provide? < < go top Possible Extension Have students construct a food web using the plankton they identified as a base. Discuss the effects on the food web if a plant or animal is removed. Include concepts such as endangered and threatened species, natural balance in a food web, and conservation and management. Students could research various local, state, and federal acts that pertain to the conservation and management of plants and animals, such as the Endangered Species Act, the Marine Mammal Protection Act, and the Magnuson-Stevens Fishery Conservation and Management Act. < < go top Teacher Evaluation Laboratory Notebook Check Laboratory Quiz/Practical Test Question #1: Viewing the slide under the microscope and using your laboratory notes, describe the organism in the field of view, and identify its scientific classification. Test Question #2: Describe in detail why it is important for scientists to know functions and purposes of their equipment when using it. < < go top