SCSA Human Biology Science Inquiry Skills
15 sample questions with marking guides and sample answers · Avg. score: 72%
A four-month investigation was undertaken in the classrooms of a large number of Year 2 and Year 3 students from four primary schools. For the first two months, half of the classes from each school used an antimicrobial gel hand sanitiser, while the other half used soap and water for regular hand hygiene. The students then switched hand-cleaning methods for the final two months. No significant differences in illness were observed between the groups.
The purpose of this investigation was most likely to
reduce water use in schools.
encourage students to wash their hands more often.
reduce the number of students who are away from school due to illness.
decide if purchasing antimicrobial gel hand sanitiser for students was worthwhile.
Reveal Answer
reduce water use in schools.
The investigation measured illness rates, not water consumption, so reducing water use was not the primary purpose of the study.
encourage students to wash their hands more often.
The study compared the effectiveness of two different hand-cleaning methods rather than trying to increase the overall frequency of handwashing.
reduce the number of students who are away from school due to illness.
Although reducing illness is a broad goal, the study specifically compared two methods to see if one was more effective, rather than just implementing a general illness reduction program.
decide if purchasing antimicrobial gel hand sanitiser for students was worthwhile.
By comparing the effectiveness of the sanitiser against standard soap and water in preventing illness, the schools could determine if the sanitiser offered enough benefit to justify its purchase.
Eloise wanted to investigate the effect of temperature changes on the basal metabolic rate of rats. According to the Australian code of practice for care and use of animals for scientific purposes, eighth edition 2013, she must follow the principles of the 3Rs for the ethical and humane care of the animals. Which of the following is not one of the 3Rs?
Replacement – that wherever possible one should use alternative approaches that do not use animals.
Reduction – one should use the smallest number of animals possible to achieve the aims and statistical design requirements.
Refinement – one should modify methodology to minimise harm to the animals.
Repetition – one should repeat the investigative approach to ensure consistent results.
Reveal Answer
Replacement – that wherever possible one should use alternative approaches that do not use animals.
Replacement is one of the 3Rs of animal ethics, which advocates for using non-animal alternatives (like computer models or cell cultures) whenever possible.
Reduction – one should use the smallest number of animals possible to achieve the aims and statistical design requirements.
Reduction is one of the 3Rs, focusing on minimizing the number of animals used in research while still obtaining statistically valid results.
Refinement – one should modify methodology to minimise harm to the animals.
Refinement is one of the 3Rs, which involves modifying experimental procedures and animal care to minimize pain, suffering, and distress.
Repetition – one should repeat the investigative approach to ensure consistent results.
Repetition is not one of the 3Rs of animal ethics. The internationally accepted 3Rs for the ethical use of animals in research are Replacement, Reduction, and Refinement.
A student designed and conducted a practical investigation to test for the presence of microbes in water and food samples.
Justify a safety precaution required to prevent infection when conducting the investigation.
Reveal Answer
The wearing of gloves to prevent contact with skin and the subsequent entry of pathogens into skin/mouth
| Descriptor | Marks |
|---|---|
Justifies a safety precaution used to prevent infection | 2 |
Provides some relevant information | 1 |
None of the above | 0 |
Explain how the student could ensure the reliability of the investigation.
Reveal Answer
The student could repeat the experiment by using five plates to culture the same sample of food or water. This would mean the student could check that the results are similar in each test.
| Descriptor | Marks |
|---|---|
Explains how to ensure the investigation is reliable | 2 |
Provides some relevant information | 1 |
None of the above | 0 |
A student completed an experiment to investigate how light is reflected from different leaves. The results were recorded qualitatively.
Which one of the following could be a correct statement about the qualitative data obtained by the student?
An average result for the data could be obtained.
The same number would be recorded for each result.
The data was obtained by measuring the wavelength of light.
The data could be the names of the different colours of the reflected light.
Reveal Answer
An average result for the data could be obtained.
Qualitative data is descriptive and non-numerical, meaning it is not possible to calculate a mathematical average from it.
The same number would be recorded for each result.
Qualitative data consists of descriptions, characteristics, or categories, rather than numerical values.
The data was obtained by measuring the wavelength of light.
Measuring the wavelength of light produces numerical values with units, which is an example of quantitative data, not qualitative.
The data could be the names of the different colours of the reflected light.
Qualitative data describes qualities or characteristics. Recording the names of the colors of reflected light is a perfect example of qualitative data.
Use the following information to answer the question.
Dengue is a disease primarily transported by mosquitoes. A group of students wish to investigate whether mosquitoes can be effectively controlled by spraying insecticide. The students will investigate the effect of spraying five different insecticides on mosquitoes.
Which one of the following techniques could the students use to generate quantitative primary data?
obtaining data from other students’ investigations
recording the smell of the five different insecticides
reading newspaper articles on the effect of insecticides on mosquitoes
measuring the mass of dead mosquitoes after spraying each insecticide
Reveal Answer
obtaining data from other students’ investigations
Obtaining data from other students' investigations is an example of collecting secondary data, not primary data.
recording the smell of the five different insecticides
Recording the smell of insecticides generates qualitative data (descriptive), not quantitative data (numerical).
reading newspaper articles on the effect of insecticides on mosquitoes
Reading newspaper articles is a method of gathering secondary data, as the information was collected and published by someone else.
measuring the mass of dead mosquitoes after spraying each insecticide
Measuring the mass of dead mosquitoes generates numerical (quantitative) data and is collected directly by the students conducting the experiment (primary data).
Use the following information to answer the question.
Dengue is a disease primarily transported by mosquitoes. A group of students wish to investigate whether mosquitoes can be effectively controlled by spraying insecticide. The students will investigate the effect of spraying five different insecticides on mosquitoes.
The students want to check the reproducibility of their results.
To do this, they should ensure that the investigation
uses only recently calibrated equipment.
has both a positive and a negative control.
is conducted by only one student, in the same laboratory.
is conducted on different days by different students.
Reveal Answer
uses only recently calibrated equipment.
Using recently calibrated equipment improves the accuracy of the measurements, but it does not test whether the experimental results can be reproduced.
has both a positive and a negative control.
Controls are essential for the validity of an experiment to ensure the independent variable is causing the observed effect, but they do not check reproducibility.
is conducted by only one student, in the same laboratory.
Having the same student perform the experiment in the same lab tests repeatability (consistency under identical conditions), not reproducibility.
is conducted on different days by different students.
Reproducibility is the ability of an experiment to be duplicated by different researchers under different conditions (such as on different days) and still yield the same results.
Use the following information to answer the question.
Students investigated the proteins found in several different types of human cells.
Students completed their investigation and analysed their results. They suggested their results were affected by systematic errors.
Systematic errors
result in a spread of readings.
affect the precision of a measurement.
are easy to identify and eliminate.
cause readings to differ from the true value by a consistent amount each time.
Reveal Answer
result in a spread of readings.
Incorrect. Random errors cause a spread or scatter of readings, whereas systematic errors shift all measurements in the same direction.
affect the precision of a measurement.
Incorrect. Systematic errors affect the accuracy of a measurement, while random errors affect its precision.
are easy to identify and eliminate.
Incorrect. Systematic errors are often difficult to identify because the measurements may still appear highly precise despite being consistently inaccurate.
cause readings to differ from the true value by a consistent amount each time.
Correct. By definition, a systematic error consistently shifts all measurements by the same amount and in the same direction from the true value.
A study assessed the effectiveness and safety of a drug called doxycycline. One hundred and fifty adults hospitalised with malaria were involved. These adults were randomly placed into two groups of equal size. One group received doxycycline in addition to standard care. The other group received standard care only.
The group receiving standard care only was the
control group.
variable group.
unsupported group.
experimental group.
Reveal Answer
control group.
The control group serves as a baseline for comparison by receiving the standard treatment without the new experimental drug.
variable group.
'Variable group' is not a standard scientific term; while variables are tested in an experiment, the groups are typically designated as control or experimental.
unsupported group.
'Unsupported group' is not a scientific term, and this group is still receiving standard medical care for their condition.
experimental group.
The experimental group is the one receiving the new intervention being tested, which in this study is the group receiving doxycycline.
Use the following information to answer the question.
A Year 12 student conducts an investigation into the effects of different amounts of water on the growth of lettuce plants. The following table outlines some aspects of the investigation.
| Lettuce plant | Amount of water (mL/day) | Temperature (°C) | Light wavelength (nm) | Percentage increase in mass of lettuce (%) |
|---|---|---|---|---|
| 1 | 150 | 10 | 660 | 5 |
| 2 | 200 | 15 | 660 | 10 |
| 3 | 250 | 20 | 660 | 15 |
| 4 | 300 | 25 | 660 | 13 |
The investigation is not considered valid because
it contains more than one dependent variable.
only lettuce is used in the investigation.
the light wavelength is set at 660 nm.
the temperature is different for each plant.
Reveal Answer
it contains more than one dependent variable.
The investigation only has one dependent variable, which is the percentage increase in mass of the lettuce.
only lettuce is used in the investigation.
Using only one type of plant is necessary to control variables and ensure a fair test, so this does not invalidate the experiment.
the light wavelength is set at 660 nm.
Keeping the light wavelength constant at 660 nm is a controlled variable, which actually supports the validity of the experiment rather than undermining it.
the temperature is different for each plant.
For an experiment to be valid, only the independent variable (amount of water) should change. Because the temperature also changes, it acts as a confounding variable, making it impossible to know whether the water or the temperature caused the difference in growth.
Students designed a controlled experiment. After they had performed the experiment, another group of students gave them feedback suggesting that they should modify the experiment to improve the accuracy of their results.
A change that the first group of students could make to improve the accuracy of their results could include
ignoring outlying results.
repeating the experiment many times.
carefully calibrating the equipment used.
having many people take the measurements.
Reveal Answer
ignoring outlying results.
Ignoring outliers does not improve accuracy and can lead to biased results; outliers should be investigated to understand their cause rather than simply discarded.
repeating the experiment many times.
Repeating the experiment many times improves the reliability and precision of the results, but it does not correct systematic errors that affect accuracy.
carefully calibrating the equipment used.
Carefully calibrating equipment reduces systematic errors, ensuring that the measurements are as close to the true value as possible, which directly improves accuracy.
having many people take the measurements.
Having multiple people take measurements introduces human variability and potential error, which can decrease precision without improving accuracy.
Use the following information to answer the question.
A bacterial plasmid was modified by inserting a gene for an enzyme that provides resistance to the antibiotic ampicillin. A nutrient solution containing cells of the bacterium Escherichia coli was obtained. E. coli is naturally sensitive to the antibiotic ampicillin. The solution was divided into two equal volumes. The bacteria in one half of the solution were left untreated. Plasmids were added to the other half of the solution and the bacteria were treated to increase their chance of taking up the plasmids.
The next day, the bacterial cells were spread on agar plates as follows:
- Plate 1 – Untreated bacterial cells on nutrient agar
- Plate 2 – Untreated bacterial cells on nutrient agar with ampicillin
- Plate 3 – Treated bacterial cells on nutrient agar with ampicillin
- Plate 4 – Treated bacterial cells on nutrient agar
The plates were incubated overnight.
In order to collect only bacterial cells that had taken up the plasmid successfully, a sample should be taken from
Plate 1.
Plate 2.
Plate 3.
Plate 4.
Reveal Answer
Plate 1.
Plate 1 contains untreated cells on plain nutrient agar. These cells were never exposed to the plasmid, and all of them will grow, so you cannot collect cells with the plasmid from this plate.
Plate 2.
Plate 2 contains untreated cells on agar with ampicillin. Since the cells naturally lack resistance and were not given the plasmid, no cells will survive or grow on this plate.
Plate 3.
Plate 3 contains treated cells on agar with ampicillin. The ampicillin acts as a selective marker, killing any cells that failed to take up the plasmid and allowing only the successfully transformed, resistant cells to grow.
Plate 4.
Plate 4 contains treated cells on plain nutrient agar. Because there is no ampicillin to kill off the unsuccessful cells, both cells that took up the plasmid and those that did not will grow together.
Prior to modern human pregnancy test kits, Xenopus frogs were used. Urine samples from women were injected into the legs of female frogs. The frogs were then placed back into water tanks and, the following day, the tanks were checked for eggs. If a female frog had laid eggs, the woman who had provided the urine sample was diagnosed to be pregnant.
Which one of the following factors may result in a false diagnosis of pregnancy?
using male frogs instead of female frogs
maintaining an optimum tank temperature
replacing the water in the tanks with fresh water each day
female frogs laying eggs naturally around the time of the injection
Reveal Answer
using male frogs instead of female frogs
Male frogs cannot lay eggs, so using them would result in a false negative (no eggs laid), rather than a false positive diagnosis of pregnancy.
maintaining an optimum tank temperature
Maintaining an optimum temperature is a standard procedure to keep the frogs healthy and capable of responding to the hormone; it does not spontaneously induce egg-laying.
replacing the water in the tanks with fresh water each day
Replacing the water is a standard husbandry practice to maintain a clean environment and would not trigger spontaneous egg-laying.
female frogs laying eggs naturally around the time of the injection
If a frog lays eggs naturally, it would appear as a positive test result even if the woman's urine did not contain pregnancy hormones, leading to a false positive diagnosis.
Refer to the information below.
A study was undertaken by which a small sequence of DNA was inserted into a virus. The virus was injected into veins of rats with Type 1 diabetes. The inserted DNA created cells that produced insulin. The purpose of this study was to find a way for humans suffering from Type 1 diabetes to eliminate the need for daily insulin injections.
Ethical approval would be required for this trial to be undertaken in humans after analysis of the results in the rat study. Which of the following would be an important ethical consideration?
number of people available to take part in the trial
possible side effects of the therapy on humans
cost of the trials
approval by drug companies
Reveal Answer
number of people available to take part in the trial
While having a sufficient sample size is important for statistical validity, the number of available participants is a logistical and scientific factor rather than a primary ethical concern.
possible side effects of the therapy on humans
The fundamental ethical principle in human trials is non-maleficence (do no harm), making the assessment of potential side effects and participant safety the most critical consideration.
cost of the trials
The financial cost of conducting a trial is an economic and administrative factor, not an ethical consideration regarding the welfare of human subjects.
approval by drug companies
Ethical approval must be granted by an independent ethics committee or institutional review board, not drug companies, to avoid conflicts of interest and ensure patient protection.
One of the ethical considerations that must be adhered to during animal research relates to when and how animals can be used. Which of the following is not part of an ethical reason to test on animals?
The research has the potential to significantly benefit humans.
The financial cost of testing on animals is less than humans.
A minimum number of animals will be used during the study.
The use of animals is essential and cannot be substituted for.
Reveal Answer
The research has the potential to significantly benefit humans.
The potential for significant human benefit is a primary ethical justification for animal research, balancing the harm to animals against the good for humanity.
The financial cost of testing on animals is less than humans.
Financial cost is a practical or economic consideration, not an ethical justification for using animals in research.
A minimum number of animals will be used during the study.
Using the minimum number of animals necessary is a key ethical principle known as 'Reduction' in the 3Rs of animal research.
The use of animals is essential and cannot be substituted for.
Ensuring that animal use is essential and cannot be replaced by non-animal alternatives is an ethical principle known as 'Replacement' in the 3Rs.
A plant specialist was investigating the viability of producing a new plant variety. The plant specialist investigated the optimum time to grow the new plant variety in Brisbane, Queensland. This plant flourishes when the temperature is above 20 °C, the precipitation is less than 50 mm per month and the number of daylight hours exceeds eight hours per day.
An example of qualitative data that the plant specialist may collect to assist their investigation of the viability of producing the new plant variety would be
recording the number of days per year that the temperature falls below 20 °C in Queensland.
determining the average number of hours of sunlight per day in Queensland.
obtaining a list of the plant preferences from people living in Brisbane.
calculating the mean monthly precipitation in Brisbane.
Reveal Answer
recording the number of days per year that the temperature falls below 20 °C in Queensland.
The number of days is a numerical count, making this quantitative discrete data rather than qualitative data.
determining the average number of hours of sunlight per day in Queensland.
The average number of hours is a numerical measurement, which represents quantitative continuous data, not qualitative data.
obtaining a list of the plant preferences from people living in Brisbane.
Plant preferences are descriptive, non-numerical categories (such as color, type, or shape), which makes this an example of qualitative data.
calculating the mean monthly precipitation in Brisbane.
Mean monthly precipitation is a numerical measurement, making it quantitative continuous data rather than qualitative data.