Scientific questions and observations

Correct answer: B. How does changing height alter leaf temperature under fixed light and airflow?

This question changes height while keeping major conditions controlled. Look for clear variables and controls when testing causation.

Correct answer: A. Morning observations may not represent the whole day

A restricted time sample may miss behaviour occurring later in the day. Check whether the observation period is representative.

Correct answer: A. Define better using average plant growth

The word better must be linked to a measurable outcome. Create operational definitions for vague terms.

Correct answer: C. Quantitative time data for the rate of change

Time must be measured to define how quickly a change occurs. Identify both change and time when studying a rate.

Correct answer: B. Use a standard colour chart under identical lighting

A standard colour reference and identical lighting reduce observer differences. Identify methods of standardisation.

Correct answer: B. Select one specific pollutant and a measurable health indicator

A broad question should be narrowed to a specific variable and measurable indicator. Check whether the scope is manageable.

Correct answer: C. The plant has a fungal infection

Fungal infection is an explanation of the cause while the number and colour of spots are observations. Identify interpretations as inferences.

Correct answer: A. The shore area may not represent the whole pond

Direct answer: Option A, the shore area may not represent the whole pond. A sample is a smaller part used to learn about a larger population. Fish may be distributed differently near the surface, bottom, deep water, plants, or open water. Observing only one shore location can therefore produce a biased estimate. Option A is correct because the chosen sample may not represent all habitats in the pond. Option B is wrong: fish can often be counted or estimated with suitable methods. Option C is wrong because pond water is not always opaque; even if visibility is poor, that is not the main sampling problem described. Option D is wrong because a count is numerical, or quantitative, data. Better sampling would include several representative locations and repeated observations. Memory cue: one place is not the whole population.

Correct answer: B. The meaning of the temperature value becomes unclear

Without a unit the numerical measurement cannot be interpreted correctly. Record a unit with every measurement.

Correct answer: C. How does the number of light hours per day affect plant height over fourteen days?

Light duration can be changed and plant height can be measured. Look for clarity of duration and outcome.

Correct answer: B. Record all birds using predefined categories

Predefined categories and recording all outcomes reduce confirmation bias. Identify unbiased recording practices.

Correct answer: B. Define clear measurement ranges for each category

Clear numerical limits allow different observers to classify rainfall consistently. Look for operational definitions of categories.

Correct answer: A. The instrument procedure and measurement conditions

Different readings may result from inconsistent instrument use or conditions. Check the procedure when repeated values vary.

Correct answer: A. Add measurable criteria for the outcome

A yes-or-no form is insufficient when the decision rule is unclear. Add explicit measurement criteria.

Correct answer: B. Use a moisture meter or a fixed mass-based method

An instrument or standardised method reduces subjective judgement. Identify ways to convert qualitative observations into quantitative ones.

Correct answer: B. How does the percentage of germinated seeds change over seven days at three temperatures?

The revised question specifies temperature levels time and germination percentage. Identify all key components.

Correct answer: A. Count movement events per minute

Counting the frequency of movement creates an operational measure of restlessness. Convert vague behaviour into countable data.

Correct answer: B. This is a preliminary observation and repetition is needed

One observation may suggest a pattern but repetition is needed for a reliable conclusion. Recognise limited evidence.

Correct answer: A. Inconsistent instruments may affect comparison

Different instrument errors may create artificial differences. Use the same or calibrated instruments.

Correct answer: B. Observe several representative locations for equal durations using the same method

Several locations and a standard method make the sample more representative and comparable. Standardise location and effort.

Correct answer: B. Time taken to dissolve

The dissolving time should be measured to define the word slowly. Convert descriptive rates into numerical data.

Correct answer: B. Parallax error

Viewing a scale from different angles can change the reading. Read liquid levels at eye height.

Correct answer: B. Change in plant dry mass over a fixed period

Dry mass can provide a clear measurable indicator of growth. Define benefit using an appropriate outcome.

Correct answer: B. Compare trunk thickness across many trees of known age

The relationship between trunk thickness and age should be tested using many trees of known age. Seek testable evidence after an inference.

Correct answer: A. When clear categories and a consistent observation method are used

Clear categories make qualitative data consistent and comparable. Do not limit scientific evidence only to numbers.