Inquiry Circles

OVERVIEW

Today inquiry teams will continue writing synthesis statements for each of their inquiry questions.

PROCEDURE

Each italicized statement below contains suggested wording the teacher may use for the lesson; additional teacher actions and considerations are in parentheses. 

Before Inquiry Circles

1. It is time to get into our inquiry circle teams. You will be with the same inquiry team as yesterday.
2. With all the questions answered on the inquiry charts, today teams will work together to write a synthesis statement about each one of your inquiry questions. You will follow the same process as we did yesterday when writing one synthesis statement for one inquiry question.
3. Choose one inquiry question at a time and write a synthesis statement as a team. (You might also give teams the option to divide up the inquiry questions and have each team member write one synthesis statement. Facilitate in a way that works best for your learners.)

During Inquiry Circles (20 minutes)

1. As you work to write your synthesis statements, remember the statement we wrote yesterday using one of the questions from the inquiry chart. (Refer to the written statement.)
2. Write your synthesis statements in your science notebooks.
3. Do not forget to use the anchor charts to help guide your thinking. (Refer to the posted anchor charts.)
4. I will help guide the inquiry circles, but I expect you to work as a team to solve your problems together. (While teams are working, walk around the room to facilitate as needed.)

After Inquiry Circles (10 minutes)

1. As we conclude our inquiry circles for today, each team will have a chance to share what they accomplished. The Lab Director will lead the discussion about today’s results Was the team able to synthesize the questions on their inquiry chart? What problems did the team encounter? How did the team resolve those problems?
2. The Data Scientists will now share with the entire class one of their team’s synthesis statements. (Try to encourage teams to share how they developed their synthesis statement. If you saw a great example in action, encourage that team to share with the entire class.)

Guided Science Investigation

Learners view a slideshow to discover how changes in a food chain such as overpopulation or  elimination of organisms can impact ecosystems.

GUIDING QUESTIONS

What happens when a producer or a consumer is added or missing from a food chain? How does a change in a food chain affect an ecosystem?

BACKGROUND INFORMATION FOR THE TEACHER

Scientists study how living and nonliving things interact in many different environments. Those environments support ecosystems unique to their surroundings and made up of food chains and food webs that provide the energy transfer necessary for the survival of life. Understanding how organisms interact and compete within an ecosystem deepens our understanding about their ecological importance in maintaining balance in the environment.

However, there are many factors that can upset the balance of an ecosystem. Some of them are natural, others are the result of natural disasters or human impact. On the most basic level, a change in a food chain can set off a series of impacts on an entire ecosystem.

When a pond is first formed it begins with mostly water and little life. As nutrients begin to enter the system, plant and animal life begins to grow and food chains develop. When organisms die, they decay and, through decomposition, release nutrients back into the pond to keep the life cycle going. The enrichment of a pond through nutrients is called eutrophication. Over decades, a pond or lake may fill up with materials, creating a wetland and, eventually, land.

Natural nutrients needed for a healthy aquatic ecosystem include carbon, oxygen, nitrogen, and phosphorous. However, animals, agriculture, and urban areas can speed up the process of eutrophication by adding excessive nutrients to the pond or lake. Too many nutrients can cause algal blooms (rapid population growth) and plant growth that directly impact food chains. Algal blooms can deplete other resources in an aquatic ecosystem. In addition, when the algae finally die, decomposers that feed on the dead algae use so much oxygen that low oxygen levels threaten fish and other members of the ecosystem.

PROCEDURE

Engage

1. Project title slide 1 of the PowerPoint. Today we’re going to take a different look at the dynamics of a pond ecosystem.
2. We’ll consider what happens when changes occur to that food chain. Remember, we are only looking at one simple food chain to illustrate the interactions between the organisms in a pond.

Explore

1. Project slide 2. Ask for volunteers to explain the food chain they see. Answers may vary but should describe the producers, consumers, and the sequence of who eats whom.
2. What do you think the light green color near the surface of the water is? (It is algae.) Remind learners that algae are so small that we only know they are present by the color of the water.
3. Explain that, overall, this appears to be a healthy ecosystem, with a good balance of organisms. In the next slides, they will see changes and will need to look closely to consider what is happening.
4. Project slide 3. Who can describe what is happening here? Can you explain the changes? (More heron, less fish, more tadpoles.) Listen to their responses, prompting as needed. (They should explain that with more heron, the population of fish goes down because the more heron eat more fish. Because there are fewer fish now, there will be more tadpoles. More tadpoles will eat more algae.)
5. Project slide 4. What changes do you see now? (No heron, lots of fish, few tadpoles, more plants, more algae.) Accept responses. Listen for their explanations to be more specific and to offer more complex explanations with fewer prompts from the teacher.
6. Are learners making connections, such as “there are more fish eating the tadpoles, so there are fewer tadpoles” and “there are more fish because there are no heron to eat them”? The fish population grows if there is nothing to eat them. However, since there are more fish, there are fewer tadpoles. What happens when the fish run out of tadpoles to eat? (Some fish may die.)
7. Did you notice there is more of the green color near the surface of the water now? Why is that? (There is more algae.) Why do you suppose there is more algae? Accept responses. Then explain that organisms can add nutrients to the water through their waste and as they rot or decay, making plants and algae grow. Nutrients are nourishments and substances found in food that help organisms survive and grow. We add nutrients like fertilizers to our lawns and plants at home for the same reason—to make them grow! (Note: a discussion of the exact nature of nutrients is not grade appropriate; however, a basic understanding of their role in ecosystem success is.)
8. Project slide #5. What has happened in the pond? Accept responses. Note: This slide may be harder for learners to analyze on their own, but it opens up the conversation for a beginning understanding of the complexity of the interactions between organisms in an ecosystem. Prompt the discussion through the possible scenarios depicted here:

• • Why did the fish die? (Because they had no food—they had used up their supply of tadpoles.) What happens to the fish when they die? (They begin to decay, and the action of decomposers releases nutrients into the water).
  • Also, there has been an algal bloom—too much algae growing faster in the water— perhaps because of too many nutrients released from the air and water; too much algae uses up the oxygen that fish and other organisms need.
  • Some plants and algae die. As bacteria breaks down the dead organisms, they use up the oxygen in the water and any remaining organisms eventually die.

Explain

1. Explain that a dead zone occurs when there is low or no oxygen left in an aquatic system. There are many things that cause the dead zones, but too many nutrients are the main cause.
2. Tell learners that besides the natural causes you have described, human activity and other sources such as fertilizers, exhaust from automobiles, wastewater, and animal waste, can make these changes occur faster by putting excessive nutrients into the water.

Elaborate

1. Remind learners that they have been looking at only one of the food chains that make up a pond ecosystem. In real life, there are many food chains that are connected in the same pond, making food webs that they will learn more about in later studies.
2. Ask them to think about the ecosystems they have been researching and learning about. How many different food chains have they discovered in the same ecosystem? Do the consumers in the food chains eat more than one thing?
3. Ask them to write 1–2 sentences in their science notebooks about how changes in the food chains might affect an ecosystem.

Evaluate

1. Did learners give a reasonable written explanation about how changes in a food chain might affect an ecosystem?
2. Did they use science language in their responses?
3. Were any connections made between the pond food chain activity and the ecosystem food chains they are researching?

Expanded Standards