What scientific methods do the students need to use to get unbiased results in their comparative investigation? (1 point)












3. Below is a list of components that can make up a number of different systems:
Sun, salmon, maple trees, bears, grass, cows, humans, shrimp, caterpillars, finches (small birds), hawks

a) Choose some of these examples, and draw a diagram of a system. Explain how the flow of matter and energy occurs through trophic levels in the system. (3 points)
Diagram a system by choosing several organisms from the list that make a food chain.
b) For the system you diagrammed in (a), give an example of a sudden change that would affect the stability of the system. Explain what may happen to food and other resources. (2 points)
Think of an example of a natural disaster or human-caused environmental change that could affect the long-term survival of the species you diagrammed in part (a).












4. Analyze the following description of a marine food chain. Use logical reasoning to find an important flaw in the description:
One abnormally short marine food chain contains only plankton and humpback whales. Unlike orcas, which hunt and eat other vertebrate animals, humpback whales have no teeth. Instead, they have baleen, which is a hard structure made of keratin — the compound that makes up your fingernails and hair. Several layers of baleen hang down from the roof of the humpback’s mouth and make a sieve. The whale swims through the ocean with its mouth open to collect plankton in the sieve. The layers of baleen must be very close together because plankton are tiny animals such as microscopic algae, crustaceans, and fish larvae. Although an adult humpback whale is 15 meters long or more, it can gather enough of these plankton to survive.
a) What is the logical error in this explanation of the humpback whale’s food chain? Describe the flow of matter and energy in the system after you’ve corrected the error. (2 points)












b) Humpbacks and orcas are both whales, one with baleen and one with teeth. How is the structure of each whale’s mouth related to what it eats? (2 points)
Think about how one part of the organism's body has evolved to do a specific job well.












5. a) List two ways that technology has had a great impact on food production in the world. (2 points)
Think about how the way you get food now differs from the way it was obtained many years ago.












b) Relate one of the technologies you listed in (a) to DNA. (1 point)
What kinds of changes in DNA have been made in plants, and why?












6. Read the following passage.

A small amount of oil contains a large amount of energy. Because of this, oil has changed the way we live since the days of horses and buggies. Our cities are built for cars, which run on gasoline made from oil. People have grown used to the idea of being able to hop in their cars and drive anywhere they want, for a relatively low price. And our country has a large network of gas stations already in place to make this possible.

However, there is only so much oil underground. As we remove the oil, it is not replaced. As it runs out, the price will increase. Also, burning oil disrupts the carbon cycle by releasing greenhouse gases. But that is not the only effect it has on the environment. Drilling for oil is a difficult process. In drilling areas, organisms can lose their homes or be killed. When oil is drilled offshore, it can cause problems for marine life. One of the worst outcomes occurs when oil is spilled into the ocean, because oil spills spread to large areas and are very difficult, or sometimes impossible, to clean up.

a) Based on this passage, analyze the pros and cons of using oil. (2 points)
List the benefits of continuing to use oil and the costs of oil drilling and burning that the passage mentions.












b) What is a consequence of disrupting the carbon cycle (by releasing greenhouse gases) or leaking carbon-rich oil into the ocean? (1 point)












c) How might society affect science and science affect society when it comes to developing better energy technology? (1 point)
Think about concerns or needs people may have.