ACT Science : Biology
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Example Questions
Example Question #101 : Act Science
Telomeres are protective caps on the ends of each strand of DNA which maintain a chromosome's integrity. Scientists believe aging may be caused by the slow degradation of these caps. Furthermore, scientists hypothesize that stress may accelerate the aging process, while other factors such as exercising and good nutrition may slow it down. To measure the aging process, scientists studied the average length of telomeres in samples drawn from three different people over the course of five years, as shown in the table below. The habits of these three people were also monitored to assess stress, exercise, and nutrition.
The overall trend for telomere length shown in the data supports which of the following hypotheses?
Telomere length decreases with increasing age
Telomere length increases with increasing age in some, while it decreases in others
Telomere length remains the same regardless of age
Telomere length decreases as a result of increasing age
Telomere length increases with increasing age
Telomere length decreases with increasing age
With one exception, telomere length decreases from year to year in all three patients. Further, from Year 1 to Year 5, there is certainly a correlation between increasing age of the three people and decreasing telomere length. Therefore, the data supports only the hypothesis that telomere length decreases with increasing age. Note that this correlation is not causation, all we know is that these two parameters follow a similar trend; we do not know if the correlation is causative.
Example Question #102 : Act Science
Telomeres are protective caps on the ends of each strand of DNA which maintain a chromosome's integrity. Scientists believe aging may be caused by the slow degradation of these caps. Furthermore, scientists hypothesize that stress may accelerate the aging process, while other factors such as exercising and good nutrition may slow it down. To measure the aging process, scientists studied the average length of telomeres in samples drawn from three different people over the course of five years, as shown in the table below. The habits of these three people were also monitored to assess stress, exercise, and nutrition.
Which of the following, if true, could explain the increase in the average telomere length of Person 3 from Year 1 to Year 2? Assume sampling error is not to blame.
Person 3 maintained a balanced diet during this time
Person 3 underwent excessive stress during this time
None of these
Strands of DNA with longer telomeres were degraded
Strands of DNA with shorter telomeres were degraded
Strands of DNA with shorter telomeres were degraded
Only the degradation of shorter telomeres would make it possible for the average length to increase. If those chromosomes with longer telomeres were degraded, the average length would decrease, not increase. As explained in the passage, excessive stress would only be likely to accelerate the shortening of the telomeres. Lastly, while a balanced diet could be at play, it would only serve to slow the shortening of the telomeres and on its own, could not explain why the average might increase.
Example Question #101 : How To Find Data Representation In Biology
Telomeres are protective caps on the ends of each strand of DNA which maintain a chromosome's integrity. Scientists believe aging may be caused by the slow degradation of these caps. Furthermore, scientists hypothesize that stress may accelerate the aging process, while other factors such as exercising and good nutrition may slow it down. To measure the aging process, scientists studied the average length of telomeres in samples drawn from three different people over the course of five years, as shown in the table below. The habits of these three people were also monitored to assess stress, exercise, and nutrition.
Given that excessive stress can accelerate aging, which person(s) likely had the most stress from Year 1 to Year 2?
Person 2 only
Person 1 only
Person 3 only
Persons 2 and 3
Persons 1 and 2
Person 1 only
If stress accelerates aging, and aging corresponds to decreasing telomere length, then the person with the largest decrease in telomere length from Year 1 to Year 2 likely had the most stress. Person 1 saw the largest decrease in length, and therefore was most likely to undergo the most stress from this data.
Example Question #102 : How To Find Data Representation In Biology
Telomeres are protective caps on the ends of each strand of DNA which maintain a chromosome's integrity. Scientists believe aging may be caused by the slow degradation of these caps. Furthermore, scientists hypothesize that stress may accelerate the aging process, while other factors such as exercising and good nutrition may slow it down. To measure the aging process, scientists studied the average length of telomeres in samples drawn from three different people over the course of five years, as shown in the table below. The habits of these three people were also monitored to assess stress, exercise, and nutrition.
From the data given, which person(s) likely maintained the most consistent level of stress, balanced diet, and proper exercise over the course of the study?
Persons 1 and 2
Person 3 only
Person 1 only
Persons 1 and 3
Person 2 only
Person 2 only
Person 2 showed the most consistent decrease in telomere length from year to year. Therefore, one can hypothesize that this person was most consistent with respect to stress, diet, and exercise since these factors have a direct impact on changing telomere length.
Example Question #101 : Biology
Scientists wanted to study the effect of different flower pollen sources on the lifespan of honey bees. They studied six different groups, each with access to a combination of two different flower types. All six groups were treated the same except for type of flower source. The table below shows the average lifespan for each control group in hours.
Which of the following flower sources leads to the longest average bee lifespan?
Cannot be determined from the data given
Daisy
Tiger lily
Sunflower
All three flowers lead to equally long bee lifespans
Sunflower
Whether combined with wildflowers or hydrangea, the sunflower bee group lived the longest on average (44.2hrs and 41.3hrs). The next highest, the tiger lily, was significantly lower when paired with wildflowers or hydrangea.
Example Question #102 : Biology
Scientists wanted to study the effect of different flower pollen sources on the lifespan of honey bees. They studied six different groups, each with access to a combination of two different flower types. All six groups were treated the same except for type of flower source. The table below shows the average lifespan for each control group in hours.
Which of the following would most improve the experiment to study different flower sources?
Place more bees in some groups than others
Place some groups in a hotter climate than others
Alter the amount of water some groups get per day
Include a control food source to be paired with each of the five flowers
Decrease the number of test flowers studied
Include a control food source to be paired with each of the five flowers
The only choice that will better the experiment is the introduction of control, through adding a control food source to be paired with each of the flowers. Differing the climate or number of bees or changing the amount of water for each group will only introduce new variables and make it more difficult to conclude anything between flower types. Decreasing the number of flowers will not necessarily make the experiment better or worse, other than losing information about the flowers that are eliminated from the study.
Example Question #102 : Biology
Scientists wanted to study the effect of different flower pollen sources on the lifespan of honey bees. They studied six different groups, each with access to a combination of two different flower types. All six groups were treated the same except for type of flower source. The table below shows the average lifespan for each control group in hours.
Which flower appeared to have a better effect on the lifespan of bees?
Both flowers had the same effect on lifespan
Wildflowers
Hydrangea
Neither flowers had an effect on lifespan
Cannot be determined from the data given
Wildflowers
For each flower type (Tiger lily, Sunflower, and Daisy), the lifespan of bees is higher when paired with Wildflowers than with Hydrangea. Therefore, with all else equal, the lifespan appears to be longer with Wildflowers than with Hydrangea.
Example Question #103 : Act Science
Scientists wanted to study the effect of different flower pollen sources on the lifespan of honey bees. They studied six different groups, each with access to a combination of two different flower types. All six groups were treated the same except for type of flower source. The table below shows the average lifespan for each control group in hours.
Which of the following statements are supported by the data?
If sunflowers are added to the combination of daisies and wildflowers, this group would exhibit the longest lifespan
Combining all five flowers will lead to the longest lifespan for the bees
When paired with tulips, daisies will result in the shortest bee lifespan as compared to tiger lillies or sunflowers
Bees will exhibit the longest lifespan when feeding on sunflowers, rather than any flower whether in the study or not
None of these
None of these
All of the answer choices rely on information not provided in the table, such as whether sunflowers are even better than flowers not studied or what will happen when combinations of flowers are used other than those shown. Therefore, none of these statements can be fully supported by the data itself.
Example Question #109 : Act Science
Researchers have recorded data in four different regions, Region A, Region B, Region C and Region D. In these regions, the researchers recorded the height, diameter and the approximate age of the tallest redwood. The researchers want to use this data to learn more amount redwoods and their respective regions.
If a tree is approximately 550 years old, what is its approximate diameter in feet?
A relationship can be noticed in the data between the diameter and the approximate age of the tree. As the age of the tree increases so does the measured diameter of the tree in all regions. In Region C, the tree has an approximate age of 500 years and a diameter of 19.4ft. Therefore if a tree had an age of 550 years, it would have a diameter that is greater than 19.4ft. The only option that is greater than 19.4ft is 20.1ft and is the correct answer.
Example Question #103 : Act Science
If you find a tree in a bright area with a height of 8.0' and a tree in a very bright area with a height of 10.1', what is the likely ground soil moisture level?
Moist
Very Dry
Dry
Very Moist
Moist
The correct answer is that the most likely ground soil moisture is moist. Following the numbers in Table 1 to the Bright and Very Bright columns, you can see that the average tree heights recorded are 7.9' and 9.7'. These averages are very close to the observed heights in the question.
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