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Example Question #161 : Act Science
A common phenomenon in aquatic plant growth and development is the effects of a limiting nutrient. A limiting nutrient is one that has the ability to stunt or halt plant growth and development if its stores are depleted in the soil or plant itself. Limiting nutrients include nitrogen and phosphorus. These nutrients are usually tightly bound to soil particles and not available for direct use. In response, plants produce and release enzymes. Enzymes release bound particles in order for the plant to actively transport nutrients from the soil. Two scientists express their views on enzyme nutrient interactions within an aquatic biome.
Scientist 1
The reaction is inducible. As the plant senses cues from phosphorus in the soil, it develops and releases enzymes to obtain the nutrients it needs. In this way, the plant obtains nutrients, preserves biological energy, and maintains fitness.
Scientist 2
The reaction is coincidental. Plants are biologically primed to create stores of phosphatase enzymes in order to obtain environmental nutrients. Therefore, fitness and energy costs are inconsequential.
Based on the information in Scientist 1's view which results would be expected in a scientific investigation of phosphatase production and plant fitness?
As plants produce enzymes, they increase levels of internal toxins as a byproduct.
As plants produce enzymes, they must utilize lactic fermentation in order to produce energy.
As plants produce enymes, they experience decreased levels of reproductive success.
As plants produce enzymes, they experience a drop in biological energy and fitness.
As plants produce enzymes, they experience a drop in biological energy and fitness.
As plants produce enzymes, they experience a drop in biological energy and fitness.
This is correct because Scientist 1 hypothesized that plants would only produce enzymes in the presence of phosporus in order to maintain proper fitness and energy levels. The other answers may or may not play a role in enzyme production but are not expectations in accordance to Scientist 1's view.
Example Question #162 : Act Science
A common phenomenon in aquatic plant growth and development is the effects of a limiting nutrient. A limiting nutrient is one that has the ability to stunt or halt plant growth and development if its stores are depleted in the soil or plant itself. Limiting nutrients include nitrogen and phosphorus. These nutrients are usually tightly bound to soil particles and not available for direct use. In response, plants produce and release enzymes. Enzymes release bound particles in order for the plant to actively transport nutrients from the soil. Two scientists express their views on enzyme nutrient interactions within an aquatic biome.
Scientist 1
The reaction is inducible. As the plant senses cues from phosphorus in the soil, it develops and releases enzymes to obtain the nutrients it needs. In this way, the plant obtains nutrients, preserves biological energy, and maintains fitness.
Scientist 2
The reaction is coincidental. Plants are biologically primed to create stores of phosphatase enzymes in order to obtain environmental nutrients. Therefore, fitness and energy costs are inconsequential.
The passage explains how plants obtain nutrients in their environments. In an environment rich in soil-bound nitrogen, which of the following would most likely be found in elevated levels within the plants?
Nitrous oxide
Endoprotease
Nitric acid
Nitrogen-fixing enzymes
Nitrogen-fixing enzymes
Nitrogen fixing enzymes
This is the correct answer because the plants would need to release the nitrogen from the soil and according to the passage a nitrogen-specific enzyme would be needed.
The plant may or may not contain nitrous oxide or nitric acid, but not as a direct consequence of soil-bound nitrogen. Last, endoprotease is an unrelated enzyme utilized in protein formation.
Example Question #163 : Act Science
A common phenomenon in aquatic plant growth and development is the effects of a limiting nutrient. A limiting nutrient is one that has the ability to stunt or halt plant growth and development if its stores are depleted in the soil or plant itself. Limiting nutrients include nitrogen and phosphorus. These nutrients are usually tightly bound to soil particles and not available for direct use. In response, plants produce and release enzymes. Enzymes release bound particles in order for the plant to actively transport nutrients from the soil. Two scientists express their views on enzyme nutrient interactions within an aquatic biome.
Scientist 1
The reaction is inducible. As the plant senses cues from phosphorus in the soil, it develops and releases enzymes to obtain the nutrients it needs. In this way, the plant obtains nutrients, preserves biological energy, and maintains fitness.
Scientist 2
The reaction is coincidental. Plants are biologically primed to create stores of phosphatase enzymes in order to obtain environmental nutrients. Therefore, fitness and energy costs are inconsequential.
Based on the information within the passages, if an aquatic biome was polluted with free-floating phosphorus, then Scientist 1 would conclude which of the following?
Plants would release phosphatase in order to acquire the newly-introduced phosphorus.
Plants would continue to obtain nutrients from the soil.
Plants would obtain phosphorus via facilitated transport of the free-floating phosphorus.
Plants would die because the phosphorus pollutants would toxify the environment.
Plants would obtain phosphorus via facilitated transport of the free-floating phosphorus.
Plants would obtain phosphorus via facilitated transport of the free-floating phosphorus.
This is the correct answer because the newly-introduced phosphorus would be easier to obtain by utilizing facilitated transport and diffusion.
Plants would die because the phosphorus pollutants would toxify the environment.
There is no evidence in the passage that this could or would occur.
Plants would continue to obtain nutrients from the soil.
Plants would not "work" to obtain phosphorus that is in exess in the environment.
Plants would release phosphatase in order to acquire the newly-introduced phosphorus.
Phosphatase would not be needed to take in already free-floating phosphorus.
Example Question #163 : Act Science
A common phenomenon in aquatic plant growth and development is the effects of a limiting nutrient. A limiting nutrient is one that has the ability to stunt or halt plant growth and development if its stores are depleted in the soil or plant itself. Limiting nutrients include nitrogen and phosphorus. These nutrients are usually tightly bound to soil particles and not available for direct use. In response, plants produce and release enzymes. Enzymes release bound particles in order for the plant to actively transport nutrients from the soil. Two scientists express their views on enzyme nutrient interactions within an aquatic biome.
Scientist 1
The reaction is inducible. As the plant senses cues from phosphorus in the soil, it develops and releases enzymes to obtain the nutrients it needs. In this way, the plant obtains nutrients, preserves biological energy, and maintains fitness.
Scientist 2
The reaction is coincidental. Plants are biologically primed to create stores of phosphatase enzymes in order to obtain environmental nutrients. Therefore, fitness and energy costs are inconsequential.
A pollutant is introduced into the environment. It acts as a competitive inhibitor to phosphatase. Therefore, it renders the phosphatase enzyme ineffective to obtain nutrients from the soil. The plant adapts to this change and produces another enzyme that is unaffected by the new pollutant. The next generation of plants possess decreased fitness and decreased reproductive success due to low numbers of offspring. Which scientist would expect these results.
Scientist 2
Scientist 1
Neither
Both
Scientist 1
Scientist 1 would expect these results because they are in agreement with his viewpoints. The plants would experience levels of decreased fitness and reproductive success because of the increased energy consumed to produce an alternative enzyme for phosphorus acquisition. Scientist 2 would not expect or support these results.
Example Question #22 : How To Find Research Summary In Biology
Passage I
An endocrinologist is a doctor who studies, diagnoses, and treats patients with hormone imbalances. There are many hormones involved in daily functioning. Two of the most important hormones for digestion are insulin and glucagon. These hormones are secreted by the pancreas. Insulin is released after a meal to help body cells take in sugar and covert it to energy. Glucagon is released when the body needs more energy, such as during exercise, and causes body cells to secrete sugar into the blood. A team of endocrinologists performed the following experiments:
Experiment 1
Five participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. All five participants were healthy and had no serious medical conditions. A team of endocrinologists monitored the blood sugar and insulin levels of the participants over time. Figure 1 is a graph of the average levels in the five participants.
Experiment 2
Two participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. One participant was healthy and the other had a hormone disease. Figure 2 is a graph of the blood sugar levels of the participants over time.
What is the most reasonable explanation for a delay between an increased level of blood glucose and an increased level of insulin?
Cells do not release insulin until they are saturated with sugar
The body takes time to digest food into sugar and signal the brain to increase insulin
Glucose levels have no impact on insulin levels
The body triggers insulin only after blood sugar reaches a specific level
The body takes time to digest food into sugar and signal the brain to increase insulin
This question can be answered by the process of elimination.
According to Figure 1, an increase in blood sugar signals an increase in insulin levels. Also, the passage states that insulin is a hormone which helps body cells take up sugar, thereby decreasing blood sugar levels. Therefore, glucose levels have an impact on insulin levels, and this answer can be eliminated.
Neither the passage nor the experiments state that cells release insulin, only blood sugar. Therefore this answer can be eliminated.
According to Figure 1, blood sugar and insulin concentrations increase gradually over time. The data indicates that there is no specific level of blood sugar that triggers insulin release; it is a continuous process. Therefore this answer can be eliminated.
This leaves only one correct answer.
Example Question #23 : How To Find Research Summary In Biology
Passage I
An endocrinologist is a doctor who studies, diagnoses, and treats patients with hormone imbalances. There are many hormones involved in daily functioning. Two of the most important hormones for digestion are insulin and glucagon. These hormones are secreted by the pancreas. Insulin is released after a meal to help body cells take in sugar and covert it to energy. Glucagon is released when the body needs more energy, such as during exercise, and causes body cells to secrete sugar into the blood. A team of endocrinologists performed the following experiments:
Experiment 1
Five participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. All five participants were healthy and had no serious medical conditions. A team of endocrinologists monitored the blood sugar and insulin levels of the participants over time. Figure 1 is a graph of the average levels in the five participants.
Experiment 2
Two participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. One participant was healthy and the other had a hormone disease. Figure 2 is a graph of the blood sugar levels of the participants over time.
If you were an endocrinologist, what would you recommend to Participant B?
Take glucagon injections to increase blood sugar levels
Nothing, Participant B is healthy
Take glucagon injections to decrease blood sugar levels
Take insulin injections to decrease blood sugar levels
Take insulin injections to increase blood sugar levels
Take insulin injections to decrease blood sugar levels
The descriptions for Experiment 1 and Experiment 2 specify the requirements for participation. Experiment 1 included all healthy individuals while Experiment 2 included one healthy and one unhealthy participant. Comparing the graphs of glucose concentration from Experiment 1 and Experiment 2, the graph of Participant A's concentration most closely resembles the graph from Experiment 1. Therefore, it is most likely that Participant B has an endocrine disease.
The graph of Paticipant B's glucose concentration is above average. Therefore, an endocrinologist would recommend Participant B take medication to lower sugar levels. The hormone which lowers blood sugar level is insulin.
Example Question #161 : Act Science
Passage I
An endocrinologist is a doctor who studies, diagnoses, and treats patients with hormone imbalances. There are many hormones involved in daily functioning. Two of the most important hormones for digestion are insulin and glucagon. These hormones are secreted by the pancreas. Insulin is released after a meal to help body cells take in sugar and covert it to energy. Glucagon is released when the body needs more energy, such as during exercise, and causes body cells to secrete sugar into the blood. A team of endocrinologists performed the following experiments:
Experiment 1
Five participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. All five participants were healthy and had no serious medical conditions. A team of endocrinologists monitored the blood sugar and insulin levels of the participants over time. Figure 1 is a graph of the average levels in the five participants.
Experiment 2
Two participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. One participant was healthy and the other had a hormone disease. Figure 2 is a graph of the blood sugar levels of the participants over time.
Which of the following patients should go see an endocrinologist?
A 14 year old boy who injured his ankle
A 55 year old woman experiencing fatigue, mood swings, and hot flashes
A 50 year old man who has very high blood sugar readings
A 3 year old toddler who needs an immunization
A 25 year old woman who has a skin rash
A 50 year old man who has very high blood sugar readings
From the passage summary, you know that an endocrinologist is a doctor who sees patients with hormone imbalances. Glucagon and insulin are hormones which control blood sugar levels. Therefore, an individual with variable blood sugar levels would most likely see an endocrinologist.
Example Question #162 : Act Science
Passage I
An endocrinologist is a doctor who studies, diagnoses, and treats patients with hormone imbalances. There are many hormones involved in daily functioning. Two of the most important hormones for digestion are insulin and glucagon. These hormones are secreted by the pancreas. Insulin is released after a meal to help body cells take in sugar and covert it to energy. Glucagon is released when the body needs more energy, such as during exercise, and causes body cells to secrete sugar into the blood. A team of endocrinologists performed the following experiments:
Experiment 1
Five participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. All five participants were healthy and had no serious medical conditions. A team of endocrinologists monitored the blood sugar and insulin levels of the participants over time. Figure 1 is a graph of the average levels in the five participants.
Experiment 2
Two participants were given 15 grams of pure glucose (sugar). The participants had not eaten for four hours prior to the experiment. One participant was healthy and the other had a hormone disease. Figure 2 is a graph of the blood sugar levels of the participants over time.
Who would an endocrinologist most likely work closely with?
Teacher
Paleontologist
Forensic Scientist
Janitor
Nutritionist
Nutritionist
From the passage, you know that an endocrinologist is a doctor who sees patients with hormone imbalances. Glucagon and insulin are two hormones which impact blood sugar levels in patients. Since an individual's diet has an impact on their sugar levels, an endocrinologist would most closely work with a nutritionist to help patients. The other choices are unlikely to work closely with an endocrinologist.
Example Question #33 : How To Find Research Summary In Biology
Invasive species lack the natural competitors in a given area to properly regulate population growth and development. Myriophyllum spicatum is a Eurasian milfoil. It was first used in the United States as an aesthetic for aquatic fish tanks. Later, it was accidentally introduced into local ponds and lakes where it became a dominant invasive species and has began to choke out native and naturally occurring plant life. To make matters worse, phosphorus-rich fertilizers and cleaners have contaminated many freshwater biomes due to runoff and pollution. As a result, many standing freshwater pools contain heavy amounts of phosphorus. These species readily utilize the phosphorus and have become nearly unmanageable. Two ecologists express their views on how to control the invasive population.
Ecologist 1
The best way to control the problem is to limit the nutrients in the biome. If the nutrients are controlled then the plants will be unable to grow and flourish. After several generations, the nutrients will be depleted and the plant species will become more manageable or disappear altogether.
Ecologist 2
The best way to control the vegetation would be to physically cut and remove it from the biome. Seasonal cuttings would minimize the population and decrease reproductive success. Furthermore, any nutrients contained in the decomposing plant litter would be removed with the waste. Therefore, after several sweeps the plants would be removed altogether.
Ecologist 2's solution was utilized because it was more cost effective. After several generations the invasive species was under control. However, the next season it grew back. How would Ecologist 1 explain this phenomenon?
The cutting of the plants only removed their upper portions and left their root systems intact. The ample amounts of nutrients in the pond permitted their quick re-growth.
The cutting was ineffective because it needed to be repeated over a longer period of time.
The non-native species is a sporophyte. The spores were released after the initial cutting and budded the next season.
The lake's pollution sustained the plants as they were being cut.
The cutting of the plants only removed their upper portions and left their root systems intact. The ample amounts of nutrients in the pond permitted their quick re-growth.
The cutting of the plants only removed their upper portions and left their root systems intact. The ample amounts of nutrients in the pond permitted their quick re-growth.
Ecologist 1 would support this statement because it is based on nutrient based growth of an invasive species. The other statements are plausible but not factually supported by Ecologist 1's ideas or methodologies.
Example Question #34 : How To Find Research Summary In Biology
Invasive species lack the natural competitors in a given area to properly regulate population growth and development. Myriophyllum spicatum is a Eurasian milfoil. It was first used in the United States as an aesthetic for aquatic fish tanks. Later, it was accidentally introduced into local ponds and lakes where it became a dominant invasive species and has began to choke out native and naturally occurring plant life. To make matters worse, phosphorus-rich fertilizers and cleaners have contaminated many freshwater biomes due to runoff and pollution. As a result, many standing freshwater pools contain heavy amounts of phosphorus. These species readily utilize the phosphorus and have become nearly unmanageable. Two ecologists express their views on how to control the invasive population.
Ecologist 1
The best way to control the problem is to limit the nutrients in the biome. If the nutrients are controlled then the plants will be unable to grow and flourish. After several generations, the nutrients will be depleted and the plant species will become more manageable or disappear altogether.
Ecologist 2
The best way to control the vegetation would be to physically cut and remove it from the biome. Seasonal cuttings would minimize the population and decrease reproductive success. Furthermore, any nutrients contained in the decomposing plant litter would be removed with the waste. Therefore, after several sweeps the plants would be removed altogether.
A japanese beetle is accidentally released into the biome. It feeds on the plant and controls its population. This provides evidence for which ecologist's theory?
Neither
Ecologist 1
Both
Ecologist 2
Neither
This provides evidence for neither ecologist. This organism happened to prey on the invasive species and solve the issue at hand. Ecologist 1 wanted to solve the problem by diverting pollution and Ecologist 2 attempted to solve the problem via physical removal of the plant. Neither suggested an organism.
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