Scribe 9/22/11

Today in class we took notes on environmental issues (section 6-3). We talked about biodiversity and how all species are involved in the food web. Some threats to biodiversity are: habitat destruction, hunting, pollution, invasive species, and global warming.
Next, we talked about global climate change and the greenhouse effect. The greenhouse effect is a natural situation where heat is trapped by CO2, methane, and other gases. It occurs from burning fossil fuels and forests. The effects of global climate change are: rising of sea level, loss of biodiversity, and natural disasters.
We also talked about Ozone Depletion. The ozone is a layer of O3 gas in the atmosphere and it filters harmful UV rays. In the 1970's, scientists found that CFC caused a hole to form in the ozone layer. CFC's were used in aerosol cans and were banned in 1987. Now, the ozone holes are shrinking! :)
Next, we talked about Pollution and Biological Magnification. DDT is a non-biodegradable pesticide, which means it can't be broken down by natural metabolic processes. Organisms cannot eliminate DDT from their bodies, which causes a decrease in population. Biological magnification is when a pollutant concentration increases higher in the food chain.
That was the end of our notes, so for the rest of the time, we met with our lab groups and discussed our duckweed presentations, which we will be presenting tomorrow during class.
The homework for tonight was:

• Practice the duckweed presentations for tomorrow!

THE NEXT SCRIBE WILL BE.... MAKENZIE :)