Analyze Design of Scientific Investigation Flashcards
When two plants, A and B, were planted together in a field outdoors, plant A produced vegetables, and plant B produced flowers which attracted pollinators. It was noted that when they were grown apart from each other, plant A did not produce vegetables, but plant B still produced flowers. Which of the following is the most likely reason plant A did not produce vegetables when planted away from plant B?
Plant B repelled harmful insects from plant A
Plant B shielded plant A from the sun
The insects that pollinated plant B also pollinated plant A
Plant B secreted a hormone that promoted the growth of plant A
The insects that pollinated plant B also pollinated plant A
Why is it important to keep most variables constant between experimental and control groups?
Keeping variables the same increases the number of experiments that can be performed so that more data can be gathered.
Minimizing changes between groups helps increase the likelihood of proving the hypothesis was correct.
Keeping most variables constant allows the effects of a single variable to be determined more accurately.
Keeping variables constant minimizes research costs.
Keeping most variables constant allows the effects of a single variable to be determined more accurately.
Dissolved oxygen (DO) is an important indicator of water quality, and oxygen levels that are too high or too low can harm aquatic ecosystems. A biologist noticed that fish were dying in a local lake and was concerned that the DO levels were too low to support aquatic life due to extremely high temperatures that summer. To measure the DO levels, she brought back several lake water samples to her laboratory to measure the DO concentration as a function of temperature. To do this, she heated several samples of lake water to various temperatures and then measured the DO concentration in each sample. Some samples were kept at the outdoors temperature.
Which is the dependent variable?
Temperature
The season
Dissolved oxygen concentration
Volume of water
Dissolved oxygen concentration
A group of students was studying the effects of drinking 8 oz. of milk at 9 p.m. on the amount of sleep they got. Which is the dependent variable?
The amount of milk
The amount of sleep
The bedtime
The time they woke up
The amount of sleep
Dissolved oxygen (DO) is an important indicator of water quality, and oxygen levels that are too high or too low can harm aquatic ecosystems. A biologist noticed that fish were dying in a local lake and was concerned that the DO levels were too low to support aquatic life due to extremely high temperatures that summer. To measure the DO levels, she brought back several lake water samples to her laboratory to measure the DO concentration as a function of temperature. To do this, she heated several samples of lake water to various temperatures and then measured the DO concentration in each sample. Some samples were kept at the outdoors temperature.
Why were some samples kept outdoors?
To act as a control group
To calibrate the thermometer
To minimize researcher bias
To allow a maximum amount of oxygen to dissolve before measurement
To act as a control group
Proper design of an experiment must maximize _______ and minimize ________.
data; error
bias; accuracy and precision
experimental variables; bias
accuracy and precision; bias
accuracy and precision; bias
Which of the following is a hypothesis?
When I added fertilizer to my plants, they grew more quickly.
One liter of water was added to a reaction.
Five different breeds of dogs are at the dog park.
If a student gets more sleep, they will get a higher test score.
If a student gets more sleep, they will get a higher test score.
A hypothesis must be which of the following?
Accurate
Precise
Testable
Correct
Testable
A biologist hypothesized that zebras and horses evolved from the same common ancestor 4 million years ago. Which of the following pieces of evidence most strongly supports this hypothesis?
Horses and zebras have similar appearances
The genome of zebras and horses are very similar to the common ancestor
Horses and zebras in similar climates
Horses and zebras gallop at the same speeds
The genome of zebras and horses are very similar to the common ancestor
H2O2 is a strong oxidizer that is used to degrade a variety of compounds. Ultraviolet-visible (UV-Vis) spectroscopy is a measurement technique that correlates the amount of UV light a substance absorbs with its concentration.
The above is background information, and the information below is the abstract of a scientific paper. Identify the hypothesis.
Pharmaceuticals have been detected in wastewaters worldwide and have the potential to harm both aquatic and human life. Traditional water treatment technologies are unable to remove these compounds from water, so various methods have been developed to degrade these compounds, including oxidation. In this paper, H2O2 is proposed to oxidatively degrade the anti-inflammatory drug, naproxen when it is dissolved in water. UV-Vis spectroscopy is used to measure the concentration of naproxen in water after samples are treated with hydrogen peroxide (H2O2). Experiments were conducted to test the influence of H2O2 concentration, reaction time, and temperature on the degradation of naproxen. The results showed that 98% of naproxen could be degraded by 0.25 M H2O2 within 2 hours at 30 oC. Thus, we can conclude that hydrogen peroxide can be used to degrade naproxen in wastewaters.
What is the the hypothesis proposed in the experiment above?
UV-Vis spectroscopy is used to measure the concentration of naproxen in water after samples are treated with hydrogen peroxide (H2O2).
Thus, we can conclude that hydrogen peroxide can be used to degrade naproxen in wastewaters.
In this paper, H2O2 is proposed to oxidatively degrade the anti-inflammatory drug, naproxen when it is dissolved in water.
Experiments were conducted to test the influence of H2O2 concentration, reaction time, and temperature on the degradation of naproxen.
In this paper, H2O2 is proposed to oxidatively degrade the anti-inflammatory drug, naproxen when it is dissolved in water.
Dissolved oxygen (DO) is an important indicator of water quality, and oxygen levels that are too high or too low can harm aquatic ecosystems. A biologist noticed that fish were dying in a local lake and was concerned that the DO levels were too low to support aquatic life due to extremely high temperatures that summer. To measure the DO levels, she brought back several lake water samples to her laboratory to measure the DO concentration as a function of temperature. To do this, she heated several samples of lake water to various temperatures and then measured the DO concentration in each sample. Some samples were kept at the outdoors temperature.
Which of the following is the independent variable?
Volume of water
Temperature
Dissolved oxygen concentration
Location of the lake
Temperature
A biologist hypothesized that high humidity environments increased the growth rate of certain bacteria. Which of the following observations refutes this hypothesis?
When placed in a dessicator, a petri dish had a decreased bacterial growth rate.
When placed next to a pond, a petri dish had an increased growth rate.
A greenhouse was found to have more bacteria compared with an outdoor garden.
Higher bacteria growth was observed in the Mojave Desert compared with the Everglades.
gher bacteria growth was observed in the Mojave Desert compared with the Everglades.
A chemist successfully synthesized an antimicrobial compound and showed that it effectively killed bacteria. The chemist then repeated this experiment two more times. What was the most likely reason for conducting this experiment three times?
To demonstrate the reproducibility of the results
To minimize researcher bias
To synthesize as much compound as possible
To kill the maximum amount of bacteria
To demonstrate the reproducibility of the results
A class of students wanted to assess the effects of coffee on test scores. What would be an appropriate control?
Drinking water during the test.
Drinking coffee immediately after the test
Not drinking coffee during the test
Drinking coffee during the test
Not drinking coffee during the test
Which of the following is a hypothesis?
A summary of experimental results that typically appears at the end of a research report.
A proposed explanation based on observation that is used to conduct further studies.
A procedure that is followed to allow a scientist to conduct a study.
The outcome of a successful experiment.
A proposed explanation based on observation that is used to conduct further studies.
