ACT Science : Biology
Study concepts, example questions & explanations for ACT Science
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Example Questions
Example Question #131 : Act Science
According to the graph, what was the population of the fish when the water temperature was hot?
High
April
Low
Cold
Hot
Low
The graph shows that as water temperature increase the fish population decreased.
Example Question #132 : Act Science
Which of the following regarding the relationship depicted on the graph is incorrect?
The maximum number of bacterial colonies occurs around 35 degrees celsius.
In general, the lower the temperature the higher the number of bacterial colonies.
The highest and lowest temperatures on the graph correlate with low numbers of bacterial colonies.
At a specific region of the graph as temperature decreases the number of bacterial colonies decreases.
At a specific region of the graph, as temperature increases the number of bacterial colonies decreases.
In general, the lower the temperature the higher the number of bacterial colonies.
All other choices can be seen from studying the graph. from studying the graph one can see that the lower the temperature, the lower the number of bacterial colonies is.
Example Question #131 : Biology
An undergraduate biology student working in a lab was reading about the latest health epidemic in the United States concerning obesity. He recently learned in his biology class that an enzyme called fatty acid synthase (FAS) catalyzes the formation of fatty acids. Accumulation of these fatty acids then creates the adipose fatty tissue that individuals typically see in their belly or side-regions. He hypothesizes that by decreasing the rate that this enzyme produces fatty acids by administering an inhibitor will aid in reducing the storage of fats, helping to alleviate obesity. After gaining approval from the university's clinical trials and ethics committee, he gathered a group of 20 test subjects. With the help of his research director, he measured the baseline rate of FAS activity for all test subjects and the averaged rate after oral administrators of a placebo and three types of inhibitors at a concentration of 0.6M to four equally-sized groups. The data is shown in Table 1.
Table 1.
The student then wonders if a mixture of different inhibitors were to increase the effect in the subject. He again measured the averaged baseline FAS level of the subjects and then attempted administering a placebo and three different combinations of inhibitors to subjects in a second trial. The results are shown in Table 2.
Table 2.
A colleague of the researcher interpreted the results from Table 1 and 2 and suggested a third trial which would track the averaged weight change of the subjects over a 6-month period. The results are shown in Table 3.
Table 3.
Based on the data tables, how could the student increase the effectiveness of Inhibitor II?
Increase the level of FAS enzyme
Couple it with Inhibitor I
None of these
Couple it with Inhibitor III
Administer a placebo in conjugation with Inhibitor II
None of these
The effectiveness of Inhibitor II is decreased when coupled to either Inhibitor I (1.04 --> 2.49), or Inhibitor III (1.04 --> 1.54) (remember that increasing rate of FAS represents a decrease in the effect of the inhibitor). Administering a placebo will have no effect regardless of the inhibitor. Increasing the level of FAS enzymes would most likely increase the rate of FAS since the inhibitor would be spread more thinly over a larger amounts of enzymes.
Example Question #131 : Act Science
An undergraduate biology student working in a lab was reading about the latest health epidemic in the United States concerning obesity. He recently learned in his biology class that an enzyme called fatty acid synthase (FAS) catalyzes the formation of fatty acids. Accumulation of these fatty acids then creates the adipose fatty tissue that individuals typically see in their belly or side-regions. He hypothesizes that by decreasing the rate that this enzyme produces fatty acids by administering an inhibitor will aid in reducing the storage of fats, helping to alleviate obesity. After gaining approval from the university's clinical trials and ethics committee, he gathered a group of 20 test subjects. With the help of his research director, he measured the baseline rate of FAS activity for all test subjects and the averaged rate after oral administrators of a placebo and three types of inhibitors at a concentration of 0.6M to four equally-sized groups. The data is shown in Table 1.
Table 1.
The student then wonders if a mixture of different inhibitors were to increase the effect in the subject. He again measured the averaged baseline FAS level of the subjects and then attempted administering a placebo and three different combinations of inhibitors to subjects in a second trial. The results are shown in Table 2.
Table 2.
A colleague of the researcher interpreted the results from Table 1 and 2 and suggested a third trial which would track the averaged weight change of the subjects over a 6-month period. The results are shown in Table 3.
Table 3.
If the researcher were attempting to closely mimic the same experimental results obtained with the placebo with one or a pair of inhibitors, which inhibitor or inhibitor pair would be sufficient?
Inhibitors II + III
Inhibitors I + II
Inhibitor I only
Inhibitor III only
Inhibitors I + III
Inhibitors I + III
The pairing of Inhibitor I and III creates a FAS rate of 2.16, which is almost identical to the rates obtained by the placebo (2.13/2.14).
Example Question #133 : How To Find Data Representation In Biology
An undergraduate biology student working in a lab was reading about the latest health epidemic in the United States concerning obesity. He recently learned in his biology class that an enzyme called fatty acid synthase (FAS) catalyzes the formation of fatty acids. Accumulation of these fatty acids then creates the adipose fatty tissue that individuals typically see in their belly or side-regions. He hypothesizes that by decreasing the rate that this enzyme produces fatty acids by administering an inhibitor will aid in reducing the storage of fats, helping to alleviate obesity. After gaining approval from the university's clinical trials and ethics committee, he gathered a group of 20 test subjects. With the help of his research director, he measured the baseline rate of FAS activity for all test subjects and the averaged rate after oral administrators of a placebo and three types of inhibitors at a concentration of 0.6M to four equally-sized groups. The data is shown in Table 1.
Table 1.
The student then wonders if a mixture of different inhibitors were to increase the effect in the subject. He again measured the averaged baseline FAS level of the subjects and then attempted administering a placebo and three different combinations of inhibitors to subjects in a second trial. The results are shown in Table 2.
Table 2.
A colleague of the researcher interpreted the results from Table 1 and 2 and suggested a third trial which would track the averaged weight change of the subjects over a 6-month period. The results are shown in Table 3.
Table 3.
What would be the best way to visualize the data in Tables 1 and 2?
A line graph with two individual lines representing either the pre or post group.
A pie chart labeling the pre and post groups with different colors.
A stem and leaf plot showing the average FAS rates.
A side-by-side bar graph with pre and post groups having different colors.
A scatter plot, comparing the pre-group and post-group on the x-axis with the change in FAS activity on the y-axis.
A side-by-side bar graph with pre and post groups having different colors.
A side-by-side bar graph would be the most clear for comparison between two groups with discrete, non-continuous results.
Example Question #131 : How To Find Data Representation In Biology
If a drug is administered intravenously (i.e. injected into a vein), then the concentration of the drug in the blood will rise and then reach a plateau. After some time, the body will begin to eliminate this drug from the bloodstream. During this elimination phase, ion pumps will actively transport some drugs from the blood into the tubules of the kidneys. Organic anion transporters (OAT) transport acids into the tubules of the kidney while organic cation transporters (OCT) transport bases into the tubules of the kidney. This mechanism, known as secretion, depends entirely on transporters and allows both acidic and basic drugs to be eliminated from the body.
Another process known as reabsorption can also occur in the kidneys. During reabsorption, drugs can be transported from the tubules of the kidney back into the blood. This process depends on the pH of the fluid in kidney tubules (e.g. the urine). At a low pH (i.e. acidic environment), acidic drugs are best reabsorbed. Conversely, at high pH (i.e. basic environment), basic drugs are best reabsorbed.
Experiment 1
The same drug was administered to various individuals. After some time elapsed, the rate of renal clearance (i.e. the rate of urine elimination from the body) was measured in each of the individuals. Subsequently, the pH of the urine was measured for each individual. The rate of renal clearance versus urinary pH was then plotted in the provided figure (each black dot represents a different individual).
Experiment 2
A scientist was able to engineer a mouse kidney that lacked organic anion transporters. She administered various drugs to the mouse and measured the rates of secretion. The data collected is located in the provided table.
An individual who has taken the drug administered in Experiment 1 has the following urinary pH:
Based on the results of Experiment 1, the rate of renal clearance for this individual would most likely be in which of the following ranges?
In Experiment 1, there were a number of individuals with urinary pH in the given range. Among these individuals, the lowest rate of renal clearance was:
The highest was:
Therefore the range would be the following:
Example Question #1 : How To Find Research Summary In Biology
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Yet, despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy. However, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Which of the following, if true, would most support Scientist 1?
Many rodents are nocturnal, but squirrels are diurnal.
Human ancestors evolved from being nocturnal to being diurnal.
Bats that are given infinite food availability sleep more.
Birds sleep in trees to avoid predators on the ground.
Bears hibernate in the winter because their food source is scarce.
Bears hibernate in the winter because their food source is scarce.
Scientist 1 claims that sleep allows animals to conserve energy during times when food is less readily available. Thus, a bear sleeping because its food is unavailable supports Scientist 1's theory.
The only other answer involving food states "Bats that are given infinite food availability sleep more." According to Scientist 1, this would mean that the bats also have unlimited energy and would require less sleep. They would not need to conserve energy if they had unlimited food.
Example Question #1 : How To Find Research Summary In Biology
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Yet, despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy. However, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Which of the following, if true, would most support Scientist 2?
Tigers that are deprived of sleep often become sick
Mother dogs often stay awake at night to guard their pups
Elephants in a herd sleep at the same time as a group
Antelope that have been injured sleep less than those that are healthy
Humans have more energy in the morning than in the evening
Tigers that are deprived of sleep often become sick
Scientist 2's theory states that "when animals are deprived of sleep, their immune system quickly weakens". Thus, when tigers are deprived of sleep, their immune systems would weaken and they would be likely to become sick.
The only other answer choice dealing with repairing damage and restoring the body is "Antelope that have been injured sleep less than those that are healthy". According to scientist 2, animals with more damage would likely sleep more to repair the damage, not less.
Example Question #2 : How To Find Research Summary In Biology
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Yet, despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy. However, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
An animal is deprived of sleep for three days. According to Scientist 1?
The animal will need to eat less food.
The animal will be prone to illness.
The animal will become nocturnal.
The animal will have low energy levels.
The animal will die.
The animal will have low energy levels.
Scientist 1 argues that sleep is necessary in order to conserve energy. Thus, if an animal is deprived of sleep, they will have lower energy.
Scientist 2, however, might argue that the animal would become sick.
Example Question #3 : How To Find Research Summary In Biology
A scientific experiment is conducted to test if calcium can affect gene regulation. Scientists hypothesize that high levels of calcium would interact with the proteins Cs3 and Gfy, which in turn would increase the transcription of genes F4597 and BC392. The experiment procedure is summarized below.
- Isolate the genes F4597 and BC392.
- Create a vector within yeast cells containing the two genes
- Culture yeast cells
- Grow yeast cells in different growth mediums—one medium lacking calcium (plate A), and one medium with supplemented calcium (plate B)
If the experiment showed that calcium increased F4597 gene activity but decreased BC392 activity, what could one conclude?
Calcium decreases the activity of protein Gfy.
The hypothesis has been disproved.
One cannot make a conclusion about the veracity of the hypothesis.
Calcium increases the activity of protein Cs3.
The hypothesis has been proved.
The hypothesis has been disproved.
The hypothesis stated the calcium manipulation would increase F4597 and BC392 activity; therefore, a result that showed decreased activity in the BC392 gene would contradict the hypothesis. Further, the hypothesis mentions that the calcium would "interact" with the proteins, but does not specific what type of interaction whether it be an increase or decrease of protein activity.
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