Using Energy

Warm up How do carbohydrates provide energy? Carbohydrates (like sugar and starch) are chemicals that have energy in the bonds that hold the atoms together. When the body breaks down sugars into simpler chemicals, energy is released.

Food and Energy Energy is a requirement of life. Light energy from the sun is captured by producer organisms during photosynthesis. Photosynthesis produces energy-rich chemicals we call food. All organisms get energy from food. Producers get energy from the food they make themselves. Consumers and decomposers get energy by eating other organisms. Energy from food is measured in calories. Calories are not ingredients in food. They are used to describe the amount of energy in food. Food calories are measured in food calories which are equal to about 1000 small calories.

Energy How do we get energy? We get energy when our bodies break down food and the energy that is stored in the bonds is released. What do you do to get new energy when you are tired? Eat! Water does not count. While it is necessary for life, it has no calories and therefore, we will eventually die with no food. Energy makes things happen. Energy is the ability to do work. What are some of the kinds of work that you do that requires energy? Discuss…..

Work What were some of the things that you came up with that? What do you do that requires energy? Lots of you said stuff like: Running, playing sports, swimming, etc. All of these fall under the category of movement because they involve body movement, movement from place to place or moving something else. One kind of work that we do is movement. What else can you think of?

Other Areas Maintenance Anything to do with the process of running or repairing the living system. Breathing, thinking, feeling, sleeping, etc. Growth and reproduction Anything that adds biomass to the system. Getting bigger, gaining weight, building muscle, producing offspring, growing hair, etc. Waste production Anything that is eliminated because it no longer has use or can be harmful. Things like waste gasses, sweating, shedding skin, etc.

Energy Use I have four categories on the board. You will work with your group to place the energy use under the proper category.

Wrap Up What do people use for energy for? Everything. All life processes require energy. When we are low on energy, what can we do? Eat food! What other ways can people get energy? There are no other ways. Trick question. Where does energy in food come from originally? The Sun!

Wrap Up How does energy from the Sun become food? Light energy is captured in photosynthesis. Carbon dioxide and water are changed into energy-rich molecules called carbohydrates. Carbohydrates are food. In which of the four categories that we used today is food produced? Growth and reproduction (mainly) Waste can be used by decomposers Read pages 14-16