Energy Flow.
Flow of energy in food chains and food webs
Beginning with some diagnostic questions about energy flow students can map their own learning during this lesson as they discover where the energy goes in a food chain and how efficient this flow is. Students construct a pryamid of energy graph to illustrate this flow and answer some IB style questions.
Lesson Description
Guiding Questions
How does energy flow from organism to organism?
Where is most of the energy found?
Where does most energy go?
Activity 1 - Diagnostic Questions about Energy
First look at this short video Biological systems depend on energy flow from the American Geosciences Institute.
For each of the Diagnostic questions on energy in food chains, select the answer which best fits your view, and then plan your justification. Once everyone has answered then share your reasons for answering the question as you did.
Try to agree with a partner which of the answers are right.
Activity 2: Explanation of pyramids energy.
This presentation contains a few simple slides of pyramids of number, biomass and energy. The can illustrate the main concepts in a class discussion or form the basis of some structured note taking. The fact that energy is lost in respiration at each trophic level can be seen in all of the diagrams. Sometimes there are problems when biomass or numbers are used. There is an activity to draw a pyramid of energy at the end.
Try to draw another pyramid of energy on drawing a pyramid of energy worksheet
Activity 3 IB Style questions on Energy flow
Try answering these IB style Questions on energy flow in ecosystems to check that you have understood these concepts well enough for the IB exams.
Teachers notes
Activity 1
Using diagnostic questions is a really powerful way to evaluate the learning needs of the class. The table can be copied onto the whiteboard and dots put into each box for the students' answers.
The exercise can be repeated at the end of the lesson to show how the students' understanding has changed, hopefully improved. This really makes learning visible.
This old activity no longer works Online animation about energy flow in food webs
Activity 2
This presentation is intended as an aid for a teacher presentation, although students could be asked to make notes from the slides, and reinforce them with their text book. The concepts covered in this lesson are not very difficulty and probably not new to most students.
Activity 3
Answers to the IB style questions can be found here:
Extra activity
For great information about animals in the Ross sea which could be used to build a food web see the Last ocean - Ross sea website