Biology

We Are All Connected:   An exploration of food webs

Grade Level- High School

Modifications could be made to make it applicable to middle or elementary levels

State Standards:

Middle School and Elementary School Standards could also be utilized if this project was modified. See standards which correlate at end of lesson.

Essential Question:

How is matter and energy transferred in a living system?

Lesson Question:

How are all living organisms dependent on each other for survival?

Introduction:

The intended audience for this project is for high school students studying ecology. The activity is to generate a food web or food chain (depending on skill level) using web 2.0 technology. An extension of the project would be to rebuild web or chain given a particular environmental change (human/ natural) that could alter the energy matter available at each tropic level.

Task:

Lesson Experiences:

TASK I - Elicit
Informally ask students if they have ever see a food web or a food chain. On the board informally brainstorm what a food web or food chain represents

5 minutes

Purpose: Helps teacher assess prior knowledge. I find that 9th grade students come from various middle schools and various levels on comprehension for each unit of Biology

Task II - Engage
FOOD WEB ANALYSIS AND DISCUSSION
Analyze the food web below. Write down 10 observations with your partner.

food web in forest

ANSWER THE FOLLOWING QUESTIONS:

  1. What is shown in the image above?
  2. Draw and label by name the organisms in the food web.
  3. Which direction do the arrows point? Why?
  4. What do the arrows represent?
  5. Which organisms have arrows pointing to them and from them? Which do not? Explain why this is.


EXPLAIN
FOLLOWING THIS ACTIVITY TEACHER LED DISCUSSION OF RESPONSES THAT LEADS INTO FORMAL LESSON PRESENTATION
This is my current ecology unit powerpoint. Please see slides 1-16

(15 minutes)

Task III - Explore
I would ask students to revisit reponses to engage activity.

  1. What do the arrows represent?
  2. Label the trophic level of each organism.
  3. Nothing is shown to eat the lion, kite, or owl. Is it true that nothing uses this organism for energy.
  4. As a class I would go over the decomposer level of a food web. This could also be a place to continue the lesson or at least weave or briefly introduce about the nitrogen cycle, carbon cycle and/or other biogeochemical cycles. Slides 17-22 on powerpoint
    (10 minutes)

  5. Add decomposers to your picture of the food web. Add arrows.
  6. Which organisms have arrows between them and the decomposers? Why?
  7. In which direction do these arrows point?

  8. EXPLAIN
    Discussion of questions 4-6 should have students realizing that all organisms are cycled back into elements to be recycled for matter for the primary producers. The decomposers are a critical organism to ensure cycling of matter in ecosystems.
    (10 minutes)

Task IV - Ellaborate

  1. In groups of 3-4 select an organism of your choice.Write down this organism and label it as a producer, consumer, or decomposer.Research using the computers what it eats and what eats it. Write information on an index card.
    Fill out index card

    EATEN BY: ________________

    ORGANISM: _______________

    TROPHIC LEVEL: _______________

    EATS: _______________

  2. Many people have mixed feeling about wikipedia. I have found that for this activity wikipedia is a valuable resource.

  3. Note webpage sources on a separate word document.
  4. Complete 7-10 index cards. Include organisms that are found at each trophic level: consumer, producer, decomposer
  5. On a large piece of paper glue index cards into a web and add arrows. Add a key to note what the arrows represent in your food web
  6. Reseach the particular biome to which your food web belongs. Add 1-3 paragraphs on your poster to note the key biotic (living) and abiotic (climate, weater, temperature, latitude...etc) features of this biome.

50 minutes

Task V- EXTEND

After the web of cards is created the students should transfer the information to a prezi and add appropriate arrows, images and descriptions. http://prezi.com/

Chemosynthetic Bacteria Food Web on Prezi

Note this could also be done instead of the poster or as an entension of the poster project. It could also be given as an individual project to completed at home with different organisms.

Further Extension: As a group discuss a situation (natural/ human caused) that could disrupt a trophic level of your food web. Using prezi, glogster, or powerpoint model how the web will be changed due to this distruption.

Conclusion:

Students will have learned the interconnectedness of organisms. Students will learn that organisms rely on other organisms in an ecosystem for matter and energy. Students will learn how to construct a food web (food chain if simplified for younger levels).
The extension can tie in environmental disasters (disease, storms…etc) or human caused harm to ecosystems. This can make the bigger picture connection that organisms are dependent on each other for survival (matter and energy) and that disruption of one trophic level can collapse the populations of many organisms in an ecosystem.

Assessments:

rubric

Resources:

Additional Standards Addressed
Middle School -

additonal standards