Lesson 4: Junk Food Calorimetry – Energy in Food Laboratory
Recall that the food which we consume provides us with energy that is needed in order of keeping our bodies alive. We need to have a constant and healthy supply of food because almost every process that happens within our bodies depends on energy. Food contains calories which provides us with sufficient energy if it is consumed in good proportions. In this laboratory experiment, students will determine the energy content in various foods and present the data in terms of kJ/g. Students will also compare their measured energy content (in kJ/g) with the energy content values given on the junk food packages
(in Calories) and will present reasons for the differences in the values.
Click on the image to the left to be redirected to the laboratory exercise retrieved from the University of Rhode Island.
(in Calories) and will present reasons for the differences in the values.
Click on the image to the left to be redirected to the laboratory exercise retrieved from the University of Rhode Island.
Lesson 5: Societal Implications
The way that heat engines works is that they gather heat from a hot reservoir and only use some of it to do work. They can only convert approximately 30 to 40 percent of the input energy. The rest is exhausted waste. The fuels that heat engines use heat engines and the process of combustion results in the emission of many harmful gases. These gases then lead to a major problem in our world: pollution.
Can you think of the advantages and disadvantages for automobiles and power plants? Focus on alternatives to some of these issues.
Can you think of the advantages and disadvantages for automobiles and power plants? Focus on alternatives to some of these issues.
Ideas for common sources of clean energy
- Wind (causes the blades of wind turbines to turn, powering generators that produce electricity)
- Geothermal energy from below Earth’s surface (used to heat buildings)
- Solar power (panels absorb radiation from the sun and convert it into electricity; the sun’s radiation can also be used to heat water)
- Hydroelectricity (the energy of moving water turns turbines to power generators that produce electricity)
- Biofuels (plant-based fuels to produce energy)
- Nuclear power (created by splitting the nuclei of atoms; this poses a new problem of radioactive waste)
You can also take your own measures and begin impacting the environment positively. It is important to recognize that all of our actions have consequences and hence taking even small steps is beneficial.
Lesson 6: Energy Transfer
In this lesson, you will learn about exothermic reaction (exergonic) and endothermic reactions (endergonic), Adenosine triphosphate (ATP) and redox reactions.
Cells need energy in order to grow, divide and repair.
Cells need energy in order to grow, divide and repair.
ATP (Adenosine triphosphate)
What is it and how it works?
ATP is a molecule in the cell that allows quick and easy access to energy when needed by the cell’s organelles. It is a type of chemical energy that releases energy when the chemical bonds are broken. ATP binds to a specific site on a protein molecule. Think about it in the sense of putting batteries in a flashlight. The molecule is utilized for energy in cells by removing a phosphate group (dephosphorylation). This produces the molecule ADP (adenosine diphosphate), which is subsequently phosphorylated to produce ATP.
Click on the image above to check out a great animation of what ATP is and how it works.
ATP is a molecule in the cell that allows quick and easy access to energy when needed by the cell’s organelles. It is a type of chemical energy that releases energy when the chemical bonds are broken. ATP binds to a specific site on a protein molecule. Think about it in the sense of putting batteries in a flashlight. The molecule is utilized for energy in cells by removing a phosphate group (dephosphorylation). This produces the molecule ADP (adenosine diphosphate), which is subsequently phosphorylated to produce ATP.
Click on the image above to check out a great animation of what ATP is and how it works.
What is a Redox Reaction?
A redox reaction is a chemical reaction involving the transfer of one or more electrons from one atom to another; a reaction in which oxidation and reduction occur. The process of losing electrons is called oxidation and the process of gaining electrons is called reduction.
Click on the image above to check out a great animation of redox reactions.
Click on the image above to check out a great animation of redox reactions.
Cell Energetics
Check out this great PowerPoint for more information on Cell Energetics.