LabLearner—The Science of Learning
LabLearner—The Science of Learning

Teacher Portal

Ecosystems

Investigation 1 – PreLab

 

 

 

 

 

 

 

Back to Investigation 1

ZERO-IN

Italicized font represents information to be shared orally or physically completed with the students at this time.

The non-italicized font represents additional information included to support the teacher’s understanding of the content being introduced within the CELL.

ASK WHY

Remind students that they depend on healthy ecosystems for their survival. Healthy ecosystems perform essential services that we depend on, including clean air, clean water, food, clothing, fuel, and lumber products. In addition, healthy ecosystems regulate floodwaters and keep lands fertile and crops pollinated.

BRANCH OUT

Remind students that marine biologists research how ocean acidification is affecting marine organisms. They also focus on migration patterns of marine mammals, photosynthesis of underwater plant life, or methods to promote coral reef protection.

GET FOCUSED

Inform students that the Investigation is designed to help them to answer the following Focus Questions:

  • How does energy move through an ecosystem? The energy at each level of an ecosystem is contained in the biomass of organisms at that level. Therefore energy is transferred from one level to another as consumers in one level eat the biomass from the level below.
  • What affects the amount of energy in an ecosystem? The amount of energy in an ecosystem is affected by the amount of energy that can be captured by plants through photosynthesis.

Note: These questions are located in students’ SDRs at the beginning and end of the Investigation.

Note: These are succinct responses to the Focus Questions and are placed here for your reference at this time. Fully developed responses to the Focus Questions can be found on the PostLab page.

GO DEEPER

As a class, read the Background(s) in the Investigation. Have students read the information aloud or silently to themselves. When students have finished, discuss the following concepts as a class:

  • The organisms in an ecosystem can be divided into two main groups: producers and consumers.
  • Producers are autotrophs, a term which means they make their own food.
  • Consumers are heterotrophs, which means they must obtain food by consuming producers or other consumers.
  • Depending on the ecosystem, there may be a different number of levels of consumers in the ecosystem.  
  • In general, the consumers in one level consume organisms from the level below. 
  • Biomass is the term scientists use to refer to the amount of dry matter in an ecosystem.
  • Dry matter is the material left after all the water has evaporated from an organism.
  • Biomass is measured in grams of dry matter per square meter (g/m2).
  • Light energy from the Sun enters an ecosystem when plants use it to perform photosynthesis.
  • Photosynthesis converts carbon dioxide and water into chemical energy.
  • The chemical energy is stored as starch or sugar. It is also used to make the structures of the plant.

Note: These concepts are integrated into the Background(s) and are used to deepen students’ comprehension of the big ideas.

LEARN THE LabLearner LINGO

The following list includes Key Terms that the teacher should introduce, as appropriate, within the CELL. These terms should be used, as appropriate, by teachers and students during everyday classroom discourse.

  • ecosystem
  • producers
  • consumers
  • detritivore
  • detritus
  • trophic level
  • biomass
  • Law of Conservation of Energy
  • Law of Conservation of Matter

Note: Definitions to these terms can be found on the Introduction page to the CELL.

Note: Additional words may be bolded within the Background(s). These words are not Key Terms and are strictly emphasized for exposure at this time.

SET FOR SUCCESS

  • Ask students to explain how photosynthesis allows plants to convert light energy into chemical energy for storage.

Note: Photosynthesis captures light energy during the conversion of carbon dioxide and water to glucose, which is stored in the plant as starch. The starch can be broken down to glucose which the plant metabolizes to release energy for growth and life processes during times when the plant is not exposed to light.

  • Tell students that ecosystems vary in the types of plants and animals that populate them. However, all ecosystems must have producers and consumers.
  • Ask students to explain the difference between producers and consumers and why both are necessary in an ecosystem.

Note: Producers are the organisms in an ecosystem that turn light energy into chemical energy that is stored in plant biomass. This chemical energy then enters the consumer levels when producers are consumed by herbivores and progresses up the ecosystem as the different consumer levels eat. Both types of organisms are needed for an ecosystem to be self-sustaining and to keep nutrients cycling through the ecosystem.

  • Explain to students that during this Investigation, they will discuss how energy moves through an ecosystem and explore how energy and biomass are related.
  • Ask students to predict whether the amount of energy in each ecosystem level is the same.

Note: Student answers will vary. Tell students that they will answer this question during their Investigation.

  • Play the video below. Stop to ask students questions or answer students’ questions when necessary. Remind students to follow along with their SDRs and make any notes that they think might be helpful.
  • After the video, direct students to divide into their lab groups to discuss their strategy for the lab. For example, they may assign certain group members to perform specific functions during the lab.

Note: The purpose of the video is to allow students to anticipate the laboratory experience they will soon encounter. Students should leave this PreLab session with a firm idea of what to expect and how to perform in the lab.

Note: Homework is posted below the video.

HOMEWORK

Tell students that they should review the Investigation in preparation for the Lab.