“Climate Science – More Than Just A Weather Report!”
First, we used the map to locate the state of Nebraska and where it is in relation to the state of California, as I introduced myself and my academic journey. Next, we asked the kids to tell us their favorite fruits, which led us to discuss the difference between and fruit and a vegetable. We started grouping the fruits into clusters according to which fruits are related (biologically) and where the fruits are grown (geographically).
Where does food come from?We talked about how plants harness the sun's energy to make sugar, and the sugar content of fruits is why we like to eat them. I wrote the chemical reaction for photosynthesis on the board. Then we talked about things like solar panels, where we use chemistry to capture energy from the sun. We used the map to talk about why certain plants are grown in the desert and other plants are grown in the mountains.
How do you get energy from food?I wrote the chemical reaction for metabolism on the board. Then I wrote the chemical reaction for combustion on the board. I emphasized that both reactions require a hydrocarbon (fuel) and oxygen, and both reactions produce carbon dioxide and water. We talked about different forms of transportation (bus, train, plane, car) and how cars can now run on gasoline, electricity, and biofuel. We talked a little about how plants consume carbon dioxide and how people consume oxygen. The kids had studied "food webs" and had a good understanding about how plants are the bottom of the food chain and how things decompose after they are no longer alive.
How does food get to you?I told the kids that I grow my own food in a garden. They have a student garden at their school, so I gave them a packet of seeds. We talked about renewable and nonrenewable sources of energy. The kids discussed this in groups and then put their conclusions on the board. They knew but didn't write that electricity comes from coal-burning. We talked about how fossil fuels were created when plants and animals died millions of years ago and became trapped under many layers of dirt. Oil, natural gas, and coal are examples of nonrenewable energy. Even using an electric car still indirectly involves combustion of fossil fuel if the electricity is generated in a coal-fired process.
The importance of innovationI told them that if we had more time, we could have talked about organic vs. non-organic foods. If we had more time, we could have talked more about the energetic cost of recycling versus mining or synthesis of new materials. We talked about aluminum and plastic and why it is better to have reusable containers. I could have encouraged them to grow their seeds in recycled "upcycled" paper cups like I do. I did tell them that they are the future of science and it would be great if they could invent more efficient processes for recycling aluminum and plastic.
Plants make more than just sugarI showed them a molecular model of capsaicin. I told them that Cayenne peppers are hot because of this molecule. I told them that capsaicin is used in pepper spray (defense) and creams for treating shingles (analgesic). If we had more time, I could have talked about how birds don't "chew" and also don't sense the heat of the hot pepper. The pepper plant relies on birds to disperse its seeds. The capsaicin molecule deters mammals from eating the pepper. Mammals chew and destroy the seeds so the plant has evolved to defend itself.
We could probably have talked more about climate change...
but as I told the kids, there's a lot to learn in college and that's a lesson for another day!