Friday, September 28, 2007

"Energy in Food"

Bellwork:
1) Two things an organism needs to survive are _____________________.
2) How does your body get the energy to do what you want it to do?

Discuss:
- We get energy from energy sources (coal, gas, wood) by burning them
- Our bodies "burn" food to get energy from it
- Heat is energy
- Food has energy

Demonstration:
- Burn cheese ball (puffcorn delite) to see if it has energy ==> if it burns and gives off heat, it has energy
- The cheese ball burns
- To measure how much energy is in the cheese ball, we burn a 2nd one under a container of water and measure how much hotter the water gets
- Results recorded on page 53 in the yellow workbook ("Measuring Food Energy")

Discuss:
- We will continue on Monday to figure out exactly how much energy there is in a cheese ball
- Key point: Food is the only way people get the energy they need to do the things they need to do