Skip Navigation

Fuel for Living Things

Author(s): Nancy P. Moreno, PhD, Barbara Z. Tharp, MS, and Judith Dresden, MS.

Fuel for Living Things

This activity uses guided inquiry to teach students that carbon dioxide is released when organisms use food, or when sugar is used for energy inside living things. Students will observe what happens when yeast cells are provided with a source of food (sugar). Students will make predictions and qualitative observations, and draw conclusions based on their investigation.


  • All organisms need a source of energy. 
  • Plants and some other organisms (producers) take in energy from the sun. 
  • All other living things rely on producers for energy and raw materials. 
  • Carbon dioxide usually is released when living things use food.

Student Worksheets

Student pages in the teacher’s guide are provided in English and in Spanish.

Funded by the following grant(s)

National Institute of Environmental Health Sciences, NIH

National Institute of Environmental Health Sciences, NIH

My Health My World: National Dissemination
Grant Number: 5R25ES009259
The Environment as a Context for Opportunities in Schools
Grant Number: 5R25ES010698, R25ES06932

Houston Endowment Inc.

Foundations for the Future: Capitalizing on Technology to Promote Equity, Access and Quality in Elementary Science Education