ACT Science : Earth and Space Sciences
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Example Question #1 : How To Find Synthesis Of Data In Earth And Space Sciences
Global warming is defined as the slow increase in the temperature of the earth’s atmosphere and is caused by pollutants and carbon dioxide (CO2). While the gradual increase in temperature cannot be refuted, scientists argue over the cause.
Scientist 1:
Global warming is caused by increases in atmospheric CO2, which is directly created by humans and their consumption of fossil fuels. The natural CO2 released from carbon sinks has a different isotopic ratio from the CO2 released from fossil fuels. Current measurements of the radioactive isotopes of CO2 show that it is from human activity, not from nature. The Earth’s carbon sinks cannot absorb these large amounts of unnatural CO2 emissions. About fifty percent of the CO2 produced by mankind remains in the atmosphere, unable to be absorbed.
Scientist 2:
The rise in atmospheric CO2 levels are a result of global warming, not the cause of it. When the temperature increases, the CO2 in carbon sinks is released. While humans do cause release of CO2, the carbon sinks absorb it. The activity of the carbon sinks increases to allow for higher levels of CO2 absorption. Proponents for human causation of global warming point to the warming and cooling of the stratosphere, however, these temperature fluctuations are caused by changes in the sun’s heat. These proponents also look at the acidity of the ocean as evidence of human causation, however, the rise in ocean acidity is within the normal range of fluctuations over the past ten thousand years.
Which of the following best outlines the evidence provided by Scientist 2 to make his argument?
Human causation, isotopic ratios, ocean acidity
Carbon sink activity, ocean acidity, and temperature changes
Carbon sink activity, ocean acidity, and isotopic ratios
Atmospheric CO2 levels, isotopic ratios, ocean acidity
Isotopic ratios, carbon sink activity, ocean acidity
Carbon sink activity, ocean acidity, and temperature changes
The only answer choice containing three topics that Scientist 2 specifically discusses is "carbon sink activity, ocean acidity, and temperature changes." Scientist 2 does not directly discuss isotope ratios, so any answer containing this option is incorrect.
Example Question #1 : How To Find Synthesis Of Data In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
A new planet is discovered 11 megaparsecs (MPSC) away from the Earth. Which of the following is its likely velocity?
Based upon the graph, an object at 11 megaparsecs should have a speed of
Example Question #3 : How To Find Synthesis Of Data In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
Two planets, one with mass 
They will have the same velocity away.
They will have different velocities, but there is insufficient data to be able to tell which will have the higher velocity.
The planet with mass 
The planet with mass 
They will have the same velocity away.
The graph gives absolutely no mention of mass. Because of that, the mass is irrelevant. The only things that the graph charts are distance away from Earth and velocity away from Earth. If they have the same distance, they will have the same velocity.
Example Question #1011 : Act Science
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
What is the acceleration on these bodies?
We need to convert kilometers to megaparsecs in order to be able to tell.
We need to know the time in order to be able to to tell.
Increasing. As they move farther away, their velocities increase.
Decreasing. While the objects are still moving away, the farther they get the less velocity they have.
Increasing. As they move farther away, their velocities increase.
Based upon the graph, the velocity increases the farther away an objects gets.
Imagine a car that drives down a highway. It starts at 10 mph, then after a mile, it increases to 20mph, then after a mile it increases to 40mph. Even though we don't know the time interval, we can assume that the vehicle is accelerating as it is moving in a roughly linear fashion.
Example Question #81 : Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
Which of the following, if true, would contradict the findings of this experiment?
A star is observed moving towards the center of the universe.
The Earth does not appear to be moving.
An incredibly hot star seems to be rotating faster than a cold star.
Stars, the same distance away, are moving away at the same speed.
A star is observed moving towards the center of the universe.
While the Earth may not "appear" to move, that's due to our relative location to it. This is much like how if you're sitting in a car driving at 60 mph, you feel like you're not moving even though your car (and you inside it) are travelling at 60 mph if observed by anyone outside of the car.
The only one of these that would directly contradict the findings would be for something to be moving towards the center of the universe as the findings point towards everything moving away.
Example Question #11 : How To Find Synthesis Of Data In Earth And Space Sciences
A scientist observes the motion of stars, planets, and other objects in deep space through a high-powered telescope. She observes that these objects all appear to be moving away from the Earth and graphs her results comparing their velocities, in kilometers per second, and their proper distance, in megaparsecs.
A second scientist observes the results of this experiment and argues we can use the results to determine the age of the universe. Is he correct?
No: we have a velocity and a distance, but no time.
No: we need more data points to be able to draw a conclusion.
Yes: we can work backwards to find the time when the time is zero and compare.
Yes: however we would need further information to be able to get an accurate conclusion.
Yes: we can work backwards to find the time when the time is zero and compare.
This graph is enough information for us to be able to solve. If you follow the units, we have a distance divided by time and then another distance unit. We can use the graph to work backwards to find the time between the beginning of the universe, when time is zero, and the current point -- approximately 14 billion years!
Example Question #11 : How To Find Synthesis Of Data In Earth And Space Sciences
Scientists studying historical trends in climate change have a number of tools at their disposal. One method of analyzing paleoclimate data involves the use of fossilized pollen spores embedded in sediment. Pollen spores are specific to the plant that produced them. Because the spores are resilient and are widely-distributed by wind, they provide a snapshot of the vegetation that was widespread at a particular point in time. By identifying the age of a sample and the composition of the various spores, scientists can identify the prominent vegetation and use this information to gain insight into the climate at the time the spores were deposited.
Scientists took sediment samples from various depths of a lakebed. They found that five types of pollen spores make up the majority of spore deposits in each sample. In Table 1, plants are listed along with the respective temperature ranges and levels of precipitation for the areas in which they are commonly found. Table 2 shows the composition of the assortment of spores in each of the four samples taken by the scientists.
A spore for a new type of plant, Plant X, is found in high concentrations in Sample 3. What is the plant's likely preferred temperature and rate of precipitation?
Temperature: 9 - 14
Precipitation: 30 - 70 cm. per year
Temperature: 14 - 20
Precipitation: 105 - 130 cm. per year
Temperature: 6 - 13
Precipitation: 125 - 155 cm. per year
Temperature: 20 - 26
Precipitation: 40 - 80 cm. per year
Temperature: 9 - 14
Precipitation: 30 - 70 cm. per year
Sample 3 has only one type of plant spore in high concentrations: Plant E. Plant X most likely has climate preferences similar to Plant E's. Both temperature and precipitation for Plant X should resemble Plant E's: 8 - 15 
Example Question #81 : Earth And Space Sciences
Scientists studying historical trends in climate change have a number of tools at their disposal. One method of analyzing paleoclimate data involves the use of fossilized pollen spores embedded in sediment. Pollen spores are specific to the plant that produced them. Because the spores are resilient and are widely-distributed by wind, they provide a snapshot of the vegetation that was widespread at a particular point in time. By identifying the age of a sample and the composition of the various spores, scientists can identify the prominent vegetation and use this information to gain insight into the climate at the time the spores were deposited.
Scientists took sediment samples from various depths of a lakebed. They found that five types of pollen spores make up the majority of spore deposits in each sample. In Table 1, plants are listed along with the respective temperature ranges and levels of precipitation for the areas in which they are commonly found. Table 2 shows the composition of the assortment of spores in each of the four samples taken by the scientists.
A fifth sample is taken at a different depth. If it contains few spores from any of the 5 plants, which is the most likely explanation for their absence?
The temperature and/or precipitation at the time was outside of the optimal ranges for each plant.
The spores did not survive from the time they were deposited.
The spores were poorly distributed.
The scientists used poor sampling procedures.
The temperature and/or precipitation at the time was outside of the optimal ranges for each plant.
According to the passage, plant populations and the concentrations of deposited spores are largely dictated by climate conditions. Therefore it is most likely that the absence of spores is also attributable to climate conditions.
The passage also states that pollen spores are resilient and widely-distributed. This makes it unlikely that they did not survive or were poorly distributed. Lastly, no changes in sampling procedures were listed besides the change in depth. Because the scientists did not find similarly low numbers in Samples 1-4, it is unlikely that their sampling procedures were the cause of the absence of spores in Sample 5.
Example Question #81 : Earth And Space Sciences
Scientists studying historical trends in climate change have a number of tools at their disposal. One method of analyzing paleoclimate data involves the use of fossilized pollen spores embedded in sediment. Pollen spores are specific to the plant that produced them. Because the spores are resilient and are widely-distributed by wind, they provide a snapshot of the vegetation that was widespread at a particular point in time. By identifying the age of a sample and the composition of the various spores, scientists can identify the prominent vegetation and use this information to gain insight into the climate at the time the spores were deposited.
Scientists took sediment samples from various depths of a lakebed. They found that five types of pollen spores make up the majority of spore deposits in each sample. In Table 1, plants are listed along with the respective temperature ranges and levels of precipitation for the areas in which they are commonly found. Table 2 shows the composition of the assortment of spores in each of the four samples taken by the scientists.
Scientists take a sample of airborne spores at the time of their collection. Assuming all five plant types are still present in the region, which would be most prevalent in the current cool, arid climate?
Plant C
Plant E
Plant A
Plant D
Plant B
Plant E
According to Table 1, the plant most tolerant of low temperatures and low precipitation is Plant E. This is most likely the most prevalent plant.
Example Question #12 : How To Find Synthesis Of Data In Earth And Space Sciences
Above is the deer population of Routt County National Forest between 1905 and 2005. The First White-tail deer were introduced to the forest for hunting in 1905. They are not native to the area, though they thrived in the environment.
White tailed deer eat the seeds of coniferous trees, berries, and an assortment of other plants. They tend to roam in small family herds and stick to areas where water is abundant and is unlikely to freeze completely in the winter.
In 1995, an environmental scientist watched a small herd of deer for ten days, recording their movements and taking note of herd size and stopping place. Below is a chart of his results.
|
Day |
Travel distance (mi) |
Herd size |
Stopping place |
|
1 |
21 |
13 |
Bear Creek |
|
2 |
15 |
13 |
Yampa Valley |
|
5 |
19 |
13 |
Bear Creek |
|
8 |
11 |
10 |
Gilpin Lake |
|
10 |
22 |
10 |
Yampa Valley |
Which of the following most likely influences where the deer herd stops when it is traveling?
High ground and tree coverage.
Access to drinking water and low ground.
Access to drinking water and access to caves.
Access to caves and low ground.
Access to drinking water and low ground.
The herd stops at creeks, lakes, and in the valley.These things all share commonalities which are, in this case, a source of water and of low ground, probably as a protection from the elements (creeks and lakes lie and the lowest points in the mountains). It would stand to reason, then, that what they are searching for is both water access as well as low ground.
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