- Published: September 26, 2022
- Updated: September 26, 2022
- University / College: University of Plymouth
- Language: English
- Downloads: 20
Even at home, many chemical reactions occur.
Ask students for some example. Possible answers/additional answers: Burning wood, lighting a stove, rusting of iron, cooking of egg. Shortly recall evidence of a chemical reaction. -color change, temperature changeSome reactions occur spontaneously and some occur non-spontaneously. Define. For a reaction to occur, the molecules of each of the reactants must collide or interact with one another.
We know from previous lessons that molecules/particles are always constantly moving. And this is due to their kinetic energy.
So for a reaction to occur and for the molecules to collide, there must be sufficient Kinetic Energy. | Listen, answer questions | Whiteboard Marker, Whiteboard| 20 mins| | Now, why are we studying chemical reactions for a biology class? That is because inside all organisms, many chemical reactions occur that are necessary for the us to survive. Ask students for one example? Give clue: how plants make food.
Other reactions in the body are: glycolysis or breaking of sugar molecules. Endergonic| Make students recall the requirements of a plant to live.
Asnwers: Light, water, air (CO2), nutrients, soil Photosynthesis occurs because a plant needs nutrients to live. During photosynthesis, CO2 + H20 react because of the presence of sunlight, the result is a glucose + oxygen. During photosynthesis, we use up energy (light) to generate sugar.
Photosyntheis therefore is an example of an “ endergonic reaction. ” DEFINE. Sugar gives us energy, right? When sugar/nutrients are synthesized further, or the process known as Glycolysis, we “ generate or produce” energy.
This is an “ exergonic reaction” – energy releasing process. Metabolism| All these processes which occur inside an organism is what we call metabolism. It consists of a network of chemical reactions often called pathways.
Two general types of pathways:(1) catabolic- breakdown complex molecules into simpler molecules.