Sr.Di's Midterm Review for:

 2. Which of the students’ hypotheses correlate with the results?
ANS: Hypothesis 2: Will increasing the percentage of carbon dioxide in the atmosphere make plants grow more rapidly?

4. The growth of plants also depends upon other factors, including temperature, soil water content, and light intensity. What should the students have done with such factors in these two experiments? Why?
ANS: They should have kept such factors constant in these experiments so that they could study the effect of only one variable on plant growth.

5.Identify the independent variable and the dependent variable in Experiment 1.
ANS: independent variable: percentage of oxygen; dependent variable: growth rate of pea plants

6. Identify the independent variable and the dependent variable in Experiment 2.
ANS: independent variable: percentage of carbon dioxide; dependent variable: growth rate of pea plants

 7. The students could have done just one experiment in which they varied both the oxygen and carbon dioxide percentages at the same time. Why do you think they chose instead to vary the oxygen and carbon dioxide percentages in separate experiments?
ANS: If they had varied both at the same time, they would not have been able to tell which gas was responsible for any change in plant growth rate they observed. By doing separate experiments, they could see the effect of varying either oxygen or carbon dioxide.

 8. Are the carbon dioxide level in the first experiment and the oxygen level in the second experiment controls, constants, dependent variables, or independent variables?  ANS: constants                     ^TOP

 10. Referring to the table above, describe the relationship between gas volume and gas pressure.
ANS: Volume decreases as pressure increases. The decrease in volume is more pronounced at lower pressures than at higher pressures.

11.While hiking along a nature trail that leads to a forest, you notice that a certain kind of plant grows deep in the forest and out in the open, away from any trees. You also notice that the appearance of the plant depends on where it grows. In the forest, the plant has large leaves and long stems. In the open, the plant has smaller leaves and short stems.

12.. Develop a hypothesis to explain this difference in the appearance of the plant.
ANS: Answers may vary. One hypothesis is that leaf size and stem length increase as the amount of light the plant receives decreases. Another hypothesis is that differences in water or nutrient content of the soils in the forest and in the open cause differences in leaf size and stem length.

 13. Design an experiment to test your hypothesis.
ANS: Answers may vary. To test the first hypothesis, plants identical to the type found along the nature trail should be grown under two or more light intensities, with other conditions held constant. To test the second hypothesis, plants identical to the type found along the nature trail should be grown in soils that differ with respect to water content or the content of a specific nutrient, with other conditions held constant. In each experiment, the leaf size and stem length of the plants grown under different conditions should be measured and compared.

14. Identify the independent and dependent variables in your experiment.              ^TOP
ANS: The independent variable depends on the hypothesis: light intensity for the first hypothesis; water content or nutrient content for the second hypothesis. The dependent variables are leaf size and stem length.

Compare and contrast each pair of related terms or phrases.
 2. lithosphere, asthenosphere
ANS: The lithosphere includes the crust and the solid uppermost part of the mantle. The asthenosphere is the partly molten layer of the mantle.

 3. independent variable, dependent variable
ANS: An independent variable is a factor that can be manipulated. A dependent variable is a factor that results from manipulating the independent variable.

 4. scientific theory, scientific law
ANS: A scientific theory is an explanation based on many observations during repeated experiments. A scientific law is a basic fact that describes the behavior of a natural phenomenon.

 6. What is studied by Earth scientists who specialize in tectonics?
ANS: Earth scientists who specialize in tectonics study the effects of internal processes on Earth’s surface, including earthquakes and mountain building.

 7. What is meant by the statement “technology is transferable”? Give an example to support the statement.
ANS: The statement means that scientific discoveries can be applied to new situations. For example, technologies used to make freeze-dried foods, ski goggles, micro-fabrics, and ultralight materials used in sports equipment were developed for use in space and were later modified for use on Earth.

 8. What should you wear during a science classroom investigation that involves pouring chemicals?
ANS: safety goggles and an apron

2. Contrast the distortion that is produced by a Mercator projection, a conic projection, and a gnomonic projection.
ANS: In a Mercator projection, the areas of landmasses near the poles are exaggerated. In a conic projection, there is very little distortion along one line of latitude, but the areas and shapes of landmasses near the top and bottom of the projection are distorted. In a gnomonic projection, the direction and distance between landmasses are distorted.

3. Which of the remote-sensing satellites discussed in Chapter 2 would be most likely to detect a large fire burning on Earth's surface? Explain your reasoning.
ANS: Landsat satellites would be most likely to detect a large fire. These satellites detect electromagnetic radiation related to warmth.

Compare and contrast each pair of related terms or phrases.
 4. latitude, longitude
ANS: Both are used to precisely locate positions on Earth. Latitude is the distance in degrees north or south of the equator. Longitude is the distance in degrees east or west of the prime meridian.

 5. conic projection, gnomonic projection
ANS: Both are ways of making a flat map by projecting points and lines from a globe. In a conic projection, the points and lines are projected onto a cone. In a gnomonic projection, the points and lines are projected onto a piece of paper that touches the globe at a single point.

 6. Landsat satellite, Topex/Poseidon satellite
ANS: Both collect data about Earth by remote sensing. A Landsat satellite detects energy related to the warmth of surface features. The Topex/Poseidon satellite uses radar to map features on the ocean floor.

 8. Why does a Mercator projection exaggerate the areas of landmasses near the poles?
ANS: Lines of longitude converge as they approach the poles, but a Mercator projection shows these lines as being parallel. Making the lines parallel stretches the area between them, especially near the poles.

 9. Why do contour lines never cross?
ANS: Each contour line represents one elevation. If two lines crossed, it would mean that the point where they crossed had two elevations, which is impossible.

 10. Why are map scales useful?
ANS: They show the relationship between distances on a map and actual distances on the surface of Earth, which enables the map reader to measure distances.

 11. How does the Topex/Poseidon satellite collect data?
ANS: The satellite sends radar waves to the ocean’s surface and picks up the echo that is reflected off the water. The distance to the water’s surface is calculated using the speed of light and the time it takes the signal to reach the surface and return. Variations in time indicate the presence of certain features on the ocean floor.

 2. Point A is located at 40°N, 75°W. Point B is located at 35°N, 120°W. When it's 10 P.M. at point A, what time is it likely to be at point B?  ANS: The difference in longitude between points A and B = 120° - 75° = 45°. Each time zone represents 1 hour and is roughly 15° wide; 45° ¸ 15° = 3 time zones or 3 hours separating points A and B. Point A is east of point B, so it is 3 hours ahead of point B. Therefore, it is likely to be 7 P.M. at point B.

 3. A mapmaker has given you a map to complete. The map already has a graphic scale and a verbal scale. The verbal scale reads, "One centimeter equals 40 kilometers." The mapmaker wants you to add the correct fractional scale. What should you write? Show your reasoning.
ANS: Since: 100 cm/m ´ 1000 m/km = 100 000 cm/km
And: 100 000 cm/km ´ 40 km = 4 000 000 cm
Then the fractional scale is 1:4 000 000.

4. The distance from Earth to Mars ranges between 78 000 000 km and 380 000 000 km, depending on the time of year. What are the advantages of using a satellite for this project instead of sending a team of astronauts to Mars to map the surface?  ANS: Answers may vary. Space flight is dangerous, and the astronauts would be risking their lives to travel to a planet that humans have not visited. It would be much more expensive to send humans to Mars and bring them back than it is to send a satellite and leave it in orbit. A satellite can collect more data more quickly while in orbit than people could on the surface. Accept all reasonable answers.

5. This map was prepared from data collected by the Mars Global Surveyor. The dashed lines on the map surround the base of the Martian volcano Olympus Mons.
                     ^TOP
6. In which hemisphere is the area on the map?
ANS: northern hemisphere

7. The circumference of Mars is 21 200 km. What is the approximate distance of each degree of latitude on Mars?  ANS:   21 200 km ¸ 360° = 58.9 km/°

8. How far does the base of Olympus Mons stretch from north to south? (Hint: Use your answer from question 5 to convert degrees to kilometers.)
ANS: The base stretches approximately 10° from north to south. 10° ´ 58.9 km/° = 589 km

9. Can you estimate how far the base of Olympus Mons stretches from east to west with the same accuracy? Explain why or why not.
ANS: No; lines of longitude get closer together as they approach the poles, but this map shows the lines as being parallel. Therefore, the map distorts distances in the east-west direction.

10. The top of Olympus Mons is the highest point on Mars. It is 27 km above the average elevation on Mars. (Because Mars has no oceans, its elevations cannot be defined with respect to sea level.) By comparison, the highest point on Earth, Mt. Everest, is 8850 m above sea level. How many times higher than Mt. Everest is Olympus Mons?                           ^TOP
ANS: 8850 m = 8.850 km; 27 km ¸ 8.850 km = 3; Olympus Mons is three times higher than Mt. Everest.

Ch.2. Give an example of a remote sensing satellite that uses active sensors, and one that uses passive sensors and contrast how these work and what information they report.

Ch.4. How do minerals form (give 2 ways) and which are most common in Earth’s crust?

Ch.11. Describe the importance of water vapor in the atmosphere.

Ch.12. What is Doppler radar, and what is it used for?

Ch.13. Describe the life cycle of a thunderstorm.

Ch.13. Compare and contrast tornadoes and hurricanes.

Ch.1. Does your area (identify your township: i.e. Arlington, Great Falls, etc.) contribute to a “Heat Island Effect” on local weather near you? Explain what the “heat island effect” is.