You will have a test on chapter 3 and the associated items we covered in class. This will include topics such as…diffusion, osmosis, special adaptations to live in fresh/salt water, counter-current exchange, skin functions, cell membrane structure, proteins within the membrane, immune system, blood types, urinary system, neurons, endocrine system and any other material in the chapter or discussed in class.
A practice test is located here.
The test will be Tuesday, March 9th.
Create a 3-dimensional model of a section of the cell membrane. (examples shown in class) This model should include all the proteins we discussed in class (non-gated, gated, carrier, pump, glycoproteins, etc…) as well as an example of an item that passes through that protein, if applicable. (i.e. sodium, alcohol, etc…) It should also include any other item in the cell membrane, such as cholesterol. You may make the model out of the material of your choosing (but not food items). You should create a separate key that denotes what each item on the model represents.
The table below shows the items you must include and what you will be graded on.
Due: Monday 3/1/10
| Parts | Diffusing Items | Overall Quality |
|---|---|---|
| phospholipid bilayer | O2, CO2, or alcohol | 3-D |
| non-gated channel/aquaporin | H2O | labeled properly (with separate key) |
| gated channel | Ion (ie. Na+) | construction quality & effort |
| carrier protein | glucose | |
| pump | Na/K | |
| glycoprotein/antigen | ||
| cholesterol |
Create a table in your Google spreadsheet that summarizes the ways various items cross the cell membrane. The table should be formatted as follows:
| Method | Items That Cross | Advantages & Disadvantages |
|---|---|---|
I have scheduled two online meetings in case you have any questions about your assignments or need any extra help. Here is how this works…
- Go to www.dimdim.com
- Click “Join Meeting” – you don’t need to register or install any special software – it should just work.
- In the “Meeting Room” box, type in “docfleetwood” (without the quotes)
- Put your name in the “Your Name” box
- Click “Join” and that should do it. If you have a microphone, you can speak to me. Otherwise there is a chat box.
The meetings are scheduled for 12:00 Friday (2/12/10) and for 11:00 Saturday (2/13/10). They are scheduled for an hour each but you can just pop in and out as you wish. So stop in and ask any questions you might have and then go about your day 
From a technological perspective, I’m interested to see how this works – so feel free to stop by and say hi even if you don’t have a question
Due to the snow and the fact that the material I want to teach you for chapter 3 is not in the book, we are going to jump to chapter 4. You task is to read chapter 4 and complete the questions in the document below. Answer the questions in the appropriate section of your notebook. This will save us time when we return to school next week.
You can print the above document directly by clicking the print icon or you can click here to open a pdf version of the same document.
Go to the following page in my wiki and explore the links on that page for more information on diffusion and osmosis through a cell membrane.
http://www.docfleetwood.net/wiki/tiki-index.php?page=Diffusion
The Earth Policy Institute issued the following press release detailing recent data on how the use of food to produce automobile fuels is affecting world starvation levels. As a society we must become more innovative in developing new methods of powering automobiles and other devices. In this new century we must let go of the antiquated combustion engine and not simply try to replace one fuel with another. The environment and the people of the world deserve better.
January 21, 2010
DATA HIGHLIGHTS – U.S. FEEDS ONE QUARTER OF ITS GRAIN TO CARS WHILE HUNGER IS ON THE RISE
http://www.earthpolicy.org/index.php?/press_room/C68/2010_datarelease6
The 107 million tons of grain that went to U.S. ethanol distilleries in 2009 was enough to feed 330 million people for one year at average world consumption levels. More than a quarter of the total U.S. grain crop was turned into ethanol to fuel cars last year. With 200 ethanol distilleries in the country set up to transform food into fuel, the amount of grain processed has tripled since 2004.
The United States looms large in the world food economy: it is far and away the world’s leading grain exporter, exporting more than Argentina, Australia, Canada, and Russia combined. In a globalized food economy, increased demand for food to fuel American vehicles puts additional pressure on world food supplies.
From an agricultural vantage point, the automotive hunger for crop-based fuels is insatiable. The Earth Policy Institute has noted that even if the entire U.S. grain crop were converted to ethanol (leaving no domestic crop to make bread, rice, pasta, or feed the animals from which we get meat, milk, and eggs), it would satisfy at most 18 percent of U.S. automotive fuel needs.
When the growing demand for corn for ethanol helped to push world grain prices to record highs between late 2006 and 2008, people in low-income grain-importing countries were hit the hardest. The unprecedented spike in food prices drove up the number of hungry people in the world to over 1 billion for the first time in 2009. Though the worst economic crisis since the Great Depression has recently brought food prices down from their peak, they still remain well above their long-term average levels.
The amount of grain needed to fill the tank of an SUV with ethanol just once can feed one person for an entire year. The average income of the owners of the world’s 940 million automobiles is at least ten times larger than that of the world’s 2 billion hungriest people. In the competition between cars and hungry people for the world’s harvest, the car is destined to win.
Continuing to divert more food to fuel, as is now mandated by the U.S. federal government in its Renewable Fuel Standard, will likely only reinforce the disturbing rise in hunger. By subsidizing the production of ethanol, now to the tune of some $6 billion each year, U.S. taxpayers are in effect subsidizing rising food bills at home and around the world.
For more information on the competition between cars and people for grain, see Chapter 2 in Plan B 4.0: Mobilizing to Save Civilization (New York: W.W. Norton & Company, 2009), on-line for free downloading with supporting datasets.
Feel free to pass this information along to friends, family members, and colleagues!
Surprises in Your Genes
Listen to this NOVA podcast regarding evolution, development and genes. As written in their own description…
In order to develop from an embryo, animals as different as fruit flies and humans call on a nearly identical set of genes. But how does this one common genetic toolkit create so many different species? It turns out that it’s not the genes you have-it’s how you use them.
Podcast produced by David Levin. Original interviews by John Rubin. NOVA is produced by WGBH in Boston. Funding for NOVA is provided by ExxonMobil, David H. Koch, the Howard Hughes Medical Institute, the Corporation for Public Broadcasting, and public television viewers.
To learn more, go to pbs.org/nova/evolution
For more NOVA ScienceNow podcasts, visit their RSS feed here.
Biology Chapter 2 Test
There will be a test on chapter 2 on Thursday, 1/14/2010. The test will include material from the textbook, the chapter question sheet and from notes covered in class.
Chapter 2 Practice Test
Need practice for chapter 2? Want to test your knowledge of energy, life and the biosphere? Take the practice test located here:
http://www.docfleetwood.net/biology/studyguides/chapter2practice.htm
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