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CCSLC Integrated Science study materials
CCSLC Integrated Science study resources

CCSLC Integrated Science practice questions

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Question 1Scientific Processes and Skills

A student records the length of a metal rod three times as 12.4 cm, 12.5 cm, and 12.4 cm. Which scientific process is the student demonstrating by taking repeated readings?

  1. Replication to improve reliability Correct answer.
  2. Classification of data
  3. Hypothesis formation
  4. Prediction of future results

Explanation

Taking repeated measurements of the same quantity improves the reliability of the result, because random variation averages out and the mean becomes more trustworthy. This is a core practical skill in scientific investigation.

Question 2Scientific Processes and Skills

In an investigation, a student changes the amount of fertilizer given to bean plants and measures the height after two weeks. What is the independent variable in this investigation?

  1. Time of two weeks
  2. Type of bean plant used
  3. Height of the plants after two weeks
  4. Amount of fertilizer given Correct answer.

Explanation

The independent variable is the factor the investigator deliberately changes. Here the student varies the amount of fertilizer, so that is the independent variable, while plant height is the dependent variable.

Question 3Scientific Processes and Skills

Which instrument is most appropriate for measuring the volume of a liquid accurately in a school laboratory?

  1. Measuring cylinder Correct answer.
  2. Balance
  3. Beaker
  4. Thermometer

Explanation

A measuring cylinder has a graduated scale designed for reading liquid volumes, so it gives a more accurate volume than a beaker. Accuracy depends on choosing an instrument whose scale matches the quantity being measured.

Question 4Scientific Processes and Skills

A student wants to know whether light is needed for a seed to germinate. Which experimental design best tests this question?

  1. Plant ten seeds in light and ten in darkness, keeping all other conditions the same Correct answer.
  2. Plant ten seeds in light and observe them for a week
  3. Compare seeds grown in warm and cold rooms without light control
  4. Plant seeds in soil and water them daily

Explanation

A fair test of light requires a control group and an experimental group that differ only in light exposure, with all other conditions such as water, temperature, and soil kept identical. This allows any difference in germination to be attributed to light.

Question 5Scientific Processes and Skills

A student measures the mass of a sample as 24.6 g, but the accepted value is 25.0 g. Which statement correctly describes the measurement?

  1. It is precise but invalid
  2. It has no error at all
  3. It is accurate but not precise
  4. It has a small error but is reasonably accurate Correct answer.

Explanation

The difference between the measured value and the accepted value is 0.4 g, which is a small error, so the measurement is reasonably accurate. Accuracy refers to closeness to the true value, while precision refers to how close repeated readings are to each other.

Question 6Scientific Processes and Skills

The table below shows four students' readings of the boiling point of water. Which set of readings is most precise?

  1. 90.0, 95.0, 100.0 degrees Celsius
  2. 75.0, 85.0, 95.0 degrees Celsius
  3. 99.8, 99.9, 99.8 degrees Celsius Correct answer.
  4. 80.0, 84.0, 88.0 degrees Celsius

Explanation

Precision is shown by how closely repeated readings agree with one another. The set 99.8, 99.9, 99.8 degrees Celsius has the smallest spread among its values, so it is the most precise.

Question 7Scientific Processes and Skills

When drawing a biological diagram of a leaf, which convention should a student follow?

  1. Include arrows showing the direction of sunlight
  2. Use clear single lines and label parts with straight ruled lines Correct answer.
  3. Draw freehand without labels
  4. Shade heavily to show texture and colour

Explanation

Scientific drawings use clear, continuous lines drawn with a sharp pencil and labels connected by straight ruled lines that do not cross. Shading and artistic effects are avoided because they obscure structure and are not part of standard biological drawing conventions.

Question 8Scientific Processes and Skills

A student writes: 'If a plant is given more water, then it will grow taller.' In which part of a scientific report would this statement most likely appear?

  1. The conclusion
  2. The apparatus list
  3. The results table
  4. The hypothesis Correct answer.

Explanation

A hypothesis is a testable prediction that links a cause to an expected effect, often written in an if-then format. The statement predicts growth from water supply, so it functions as a hypothesis.

Question 9Scientific Processes and Skills

A student places a ruler at the edge of a table and measures the length of a pencil as 8.2 cm. Which improvement would most reduce measurement error?

  1. Reading the scale from an angle
  2. Aligning the eye directly above the scale and starting from the zero mark Correct answer.
  3. Estimating the length without a ruler
  4. Using a ruler with a worn end and starting from the edge

Explanation

Parallax error occurs when the eye is not directly above the scale, and a worn end introduces a zero error. Aligning the eye and starting from the zero mark reduces both sources of error, giving a more reliable reading.

Question 10Scientific Processes and Skills

A student classifies a set of animals into two groups based on whether they have a backbone. Which scientific process is being used?

  1. Modelling
  2. Prediction
  3. Classification Correct answer.
  4. Hypothesis testing

Explanation

Classification is the process of grouping organisms or objects according to shared characteristics. Sorting animals by the presence of a backbone uses a single defining feature, which is a form of classification.

Question 11Scientific Processes and Skills

A graph of plant height against days shows a straight line rising from 2 cm to 10 cm over 8 days. What is the rate of growth?

  1. 0.5 cm per day
  2. 8.0 cm per day
  3. 2.0 cm per day
  4. 1.0 cm per day Correct answer.

Explanation

The rate of growth is the change in height divided by the change in time. The height increases by 8 cm over 8 days, giving a rate of 1.0 cm per day.

Question 12Scientific Processes and Skills

In an investigation, the same experiment is carried out by three different groups in different schools, and they obtain similar results. What does this best demonstrate?

  1. That the results are reproducible Correct answer.
  2. That no further investigation is needed
  3. That the hypothesis is proven true
  4. That the equipment was faulty

Explanation

When independent investigators repeat an experiment and obtain similar results, the findings are reproducible, which strengthens confidence in them. Reproducibility is a key feature of reliable scientific evidence.

Question 13Scientific Processes and Skills

A student uses a bar chart to display the number of each type of insect caught in a trap. Why is a bar chart appropriate for this data?

  1. The data show a relationship between two measured variables
  2. The data are counts in separate categories Correct answer.
  3. The data are continuous measurements over time
  4. The data are recorded as percentages of a whole

Explanation

Bar charts suit categorical data, where each bar represents a distinct group and its height shows a count or frequency. Insect types are separate categories, so a bar chart displays them clearly.

Question 14Scientific Processes and Skills

A result is described as an anomaly. What should a scientist do with it?

  1. Change it to match the other readings
  2. Use it as the main conclusion
  3. Include it and investigate its possible cause Correct answer.
  4. Ignore it and delete it from the record

Explanation

An anomalous result is one that does not fit the pattern of the other data. Good practice is to record it honestly and investigate its cause, such as a measurement error, rather than hiding or altering it.

Question 15Scientific Processes and Skills

A student wants to test how the concentration of acid affects the rate of reaction with marble chips. Which factor must be kept constant to make the test fair?

  1. The volume of gas produced
  2. The rate of reaction measured
  3. The mass of marble chips used Correct answer.
  4. The concentration of the acid

Explanation

In a fair test only the independent variable, here acid concentration, is changed. The mass of marble chips is a controlled variable and must remain the same so that any change in rate can be attributed to concentration.

Question 16Scientific Processes and Skills

A student measures the temperature of a liquid with a thermometer and reads 25 degrees Celsius. Which statement best describes the role of the thermometer in this investigation?

  1. It is the independent variable
  2. It is the instrument used to measure the dependent variable Correct answer.
  3. It is a source of random error only
  4. It is a control variable

Explanation

Instruments are used to measure the dependent variable, which is the outcome being recorded. The thermometer provides the temperature reading, so it measures the dependent variable.

Question 17Scientific Processes and Skills

Which of the following is the best example of a testable scientific question?

  1. Why is the sky beautiful?
  2. Should students be allowed to choose their science topics?
  3. Does the colour of light affect the rate of photosynthesis in pondweed? Correct answer.
  4. Is it wrong to keep animals in cages?

Explanation

A testable question can be investigated through observation and measurement and has variables that can be manipulated. Asking whether light colour affects photosynthesis identifies a variable that can be changed and a measurable outcome.

Question 18Scientific Processes and Skills

A student records the following results: 5.0, 5.2, 4.9, 5.1, and 12.5. What is the most appropriate next step in analysing these data?

  1. Conclude that the experiment failed
  2. Identify 12.5 as an anomaly and investigate it before calculating a mean Correct answer.
  3. Calculate the mean including all five values
  4. Discard the four lowest readings

Explanation

The value 12.5 is far from the other four readings, which cluster around 5.0, so it is likely an anomaly. Identifying and checking it before averaging prevents the mean from being distorted by an unusual value.

Question 19Scientific Processes and Skills

A student claims that a plant grew faster because it was spoken to daily. Which additional evidence would most strengthen this claim?

  1. A second group of identical plants grown without being spoken to Correct answer.
  2. A description of the plant's colour
  3. A photograph of the plant that was spoken to
  4. An estimate of the plant's height made by eye

Explanation

To support a causal claim, a control group is needed that differs only in the factor being tested. Identical plants not spoken to provide a comparison, showing whether the growth difference is due to the talking.

Question 20Scientific Processes and Skills

A student uses a scale with a zero error, so every reading is 0.5 g too high. What type of error is this and how can it be corrected?

  1. Systematic error, corrected by taking the highest reading
  2. Random error, corrected by repeating readings many times
  3. Systematic error, corrected by subtracting 0.5 g from each reading Correct answer.
  4. Random error, corrected by using a different balance

Explanation

A zero error affects every reading by the same amount, so it is a systematic error rather than a random one. It can be corrected by subtracting the fixed offset from each reading or by re-zeroing the balance.

Question 21Scientific Processes and Skills

A line graph shows the temperature of a cooling liquid falling steeply and then levelling off. What does the levelling off most likely indicate?

  1. The liquid has reached the temperature of its surroundings Correct answer.
  2. The thermometer has broken
  3. The experiment has just begun
  4. The liquid is now boiling

Explanation

A cooling curve flattens when the temperature difference between the liquid and its surroundings becomes small, so the rate of heat loss slows. The liquid approaches room temperature and stops falling further.

Question 22Scientific Processes and Skills

A student wants to estimate the area of an irregular leaf. Which method is most appropriate?

  1. Multiply the leaf's length by its width
  2. Measure the mass of the leaf on a balance
  3. Measure the perimeter with a ruler
  4. Trace the leaf onto squared paper and count the squares covered Correct answer.

Explanation

Tracing the outline onto squared paper and counting the full and partial squares gives a reasonable estimate of an irregular area. The square-counting method is a standard practical technique for irregular shapes.

Question 23Scientific Processes and Skills

In an investigation into how exercise affects heart rate, a student measures the pulse rate of ten classmates before and after one minute of running. Which conclusion is best supported if pulse rates rise in all ten students?

  1. Heart rate has no relationship with exercise
  2. Running is unhealthy for all people
  3. The students were unfit
  4. Running causes an increase in heart rate in these students Correct answer.

Explanation

A consistent increase across all participants supports the conclusion that running raises heart rate in this group. Conclusions should be limited to what the evidence shows, which is a rise in pulse rate after exercise.

Question 24Scientific Processes and Skills

A student's results table lacks units and column headings. Why is this a problem in scientific reporting?

  1. It changes the actual values recorded
  2. It prevents readers from knowing what was measured and in what units Correct answer.
  3. It makes the table look untidy
  4. It makes the experiment unfair

Explanation

Units and headings tell the reader what quantity was measured and on what scale, which is essential for interpreting and repeating the work. Without them the numbers have no clear meaning.

Question 25Scientific Processes and Skills

Two students measure the same block. Student A reports 45.2 g using a balance reading to 0.1 g. Student B reports 45 g using the same balance. Which report is better and why?

  1. Student A, because the reading matches the precision of the balance Correct answer.
  2. Student B, because a whole number is easier to read
  3. Both are equally good because the mass is the same
  4. Student B, because fewer digits reduce error

Explanation

A measurement should be reported to the precision the instrument allows. Since the balance reads to 0.1 g, recording 45.2 g reflects that precision, whereas 45 g discards information the instrument provided.

Question 26Scientific Processes and Skills

A student wants to find out whether the type of soil affects how quickly bean seeds germinate. Which variable should be kept the same in every pot?

  1. The type of soil in each pot
  2. The number of days each seed takes to germinate
  3. The height of the seedling after one week
  4. The amount of water given to each pot Correct answer.

Explanation

A fair test changes only the independent variable (soil type) and keeps all other conditions constant so that any difference in outcome can be attributed to the soil. Water is a controlled variable here because it could independently affect germination. The days to germinate and the seedling height are measured outcomes, not conditions to hold constant.

Question 27Scientific Processes and Skills

In a scientific investigation, what is the main purpose of repeating a measurement several times?

  1. To make the experiment take longer
  2. To change the independent variable
  3. To reduce the effect of random variation on the result Correct answer.
  4. To prove the hypothesis is true

Explanation

Repeated readings allow a mean to be calculated, which smooths out random fluctuations and gives a more reliable value. Repeats do not by themselves prove a hypothesis; they simply improve confidence in the data. They also do not alter what is being tested.

Question 28Scientific Processes and Skills

A student reads a burette and records the volume as 24.5 cm3. A second student, using the same burette, records 24.6 cm3. What does this small difference best illustrate?

  1. A systematic error in the burette
  2. A change in the independent variable
  3. Random error in reading the scale Correct answer.
  4. A fault in the experimental design

Explanation

Small differences between repeated readings by different observers arise from random error, such as slight variation in judging the meniscus. Random error scatters results around the true value and can be reduced by averaging. A systematic error would shift all readings in the same direction by the same amount.

Question 29Scientific Processes and Skills

Which statement best describes the difference between an observation and an inference?

  1. An observation is what is directly sensed; an inference is a conclusion drawn from it Correct answer.
  2. An observation is a guess; an inference is a measurement
  3. An observation is always numerical; an inference is always descriptive
  4. An observation is recorded after an inference is made

Explanation

An observation records information gathered directly through the senses or instruments, while an inference is an interpretation or explanation based on that information. For example, seeing bubbles is an observation, whereas concluding that a gas is being produced is an inference. The other statements confuse the two terms.

Question 30Scientific Processes and Skills

A student measures the mass of five identical steel balls and obtains 12.1 g, 12.0 g, 12.2 g, 12.1 g and 12.0 g. The accepted value is 11.0 g. Which statement about these results is correct?

  1. The results are both accurate and precise
  2. The results are neither accurate nor precise
  3. The results are accurate but not precise
  4. The results are precise but not accurate Correct answer.

Explanation

Precision refers to how closely repeated measurements agree with each other, and these readings cluster tightly around 12.1 g. Accuracy refers to how close a measurement is to the accepted value, and all readings are about 1 g above 11.0 g. The results are therefore precise but inaccurate, suggesting a systematic error.

Question 31Scientific Processes and Skills

A student wants to determine how the length of a pendulum affects its period. Which is the independent variable in this investigation?

  1. The mass of the pendulum bob
  2. The angle of release
  3. The length of the pendulum Correct answer.
  4. The period of the pendulum

Explanation

The independent variable is the factor deliberately changed by the investigator, which here is the pendulum length. The period is the dependent variable because it is measured in response. The mass of the bob and the angle of release are controlled variables that must be kept constant.

Question 32Scientific Processes and Skills

A student plots a graph of gas volume produced against time and draws a smooth curve of best fit rather than joining each point with straight lines. Why is a line of best fit preferred?

  1. It hides any points that do not fit the pattern
  2. It guarantees that every measurement was correct
  3. It shows the overall trend while accounting for random scatter in the data Correct answer.
  4. It converts the data into a different unit

Explanation

A line or curve of best fit summarises the underlying trend and allows for small random variations in individual readings. It does not remove or conceal genuine anomalies, which should still be identified. Drawing the line does not change the data or the units.

Question 33Scientific Processes and Skills

A student wants to compare the proportion of time four different activities occupy in a school day. Which type of graph or chart is most suitable?

  1. A line graph
  2. A pie chart Correct answer.
  3. A scatter graph
  4. A histogram

Explanation

A pie chart displays parts of a whole as sectors, so it is well suited to showing proportions of a total such as the hours in a day. Line graphs show change over time, scatter graphs show the relationship between two variables, and histograms show the frequency distribution of continuous data.

Question 34Scientific Processes and Skills

A student measures the length of a metal rod as 25.4 cm using a ruler marked in millimetres. Which statement best describes the uncertainty in this reading?

  1. The uncertainty is 25.4 cm because that is the reading
  2. The uncertainty is zero because the ruler has markings
  3. The uncertainty is 1 cm because the ruler is one metre long
  4. The uncertainty is about 0.1 cm because the ruler has millimetre markings Correct answer.

Explanation

The uncertainty of a single reading is typically about half the smallest scale division, or roughly one division for a ruler read to the nearest millimetre. A ruler marked in millimetres therefore gives an uncertainty of about 0.1 cm. Uncertainty is never zero when using an analogue scale.

Question 35Scientific Processes and Skills

A student writes a conclusion that states 'the higher the temperature, the faster the reaction'. Which feature makes this conclusion scientifically weak on its own?

  1. It is shorter than the method section
  2. It uses the word reaction
  3. It is written in the present tense
  4. It does not refer to the evidence collected or to the range of temperatures tested Correct answer.

Explanation

A sound conclusion links the pattern claimed to the actual data collected and states the range over which it applies. Without reference to evidence or the temperatures tested, the statement is an unsupported generalisation. The tense, vocabulary and length are not what determine scientific strength.

Question 36Scientific Processes and Skills

In an investigation, a student measures the growth of a plant every day at 9 a.m. under the same lamp. Which term best describes the daily 9 a.m. timing and the lamp setting?

  1. Controlled variables Correct answer.
  2. Dependent variables
  3. Independent variables
  4. Anomalous results

Explanation

Conditions deliberately kept the same for every trial are controlled variables, and here both the time of measurement and the lamp setting are held constant. The dependent variable would be the plant growth being measured. The independent variable would be whatever factor the student deliberately changes.

Question 37Scientific Processes and Skills

A student records the following readings for the time of 20 swings of a pendulum: 20.1 s, 20.0 s, 20.2 s, 20.1 s and 20.1 s. What is the mean time for 20 swings, and what is the mean time for one swing?

  1. 20.1 s for 20 swings and 20.1 s for one swing
  2. 20.0 s for 20 swings and 1.00 s for one swing
  3. 20.1 s for 20 swings and 0.1005 s for one swing
  4. 20.1 s for 20 swings and 1.005 s for one swing Correct answer.

Explanation

The mean of the five readings is (20.1 + 20.0 + 20.2 + 20.1 + 20.1) / 5 = 20.1 s. Dividing by 20 swings gives 20.1 / 20 = 1.005 s per swing. This shows how averaging and then dividing by the number of swings improves the reliability of a timing result.

Question 38Scientific Processes and Skills

A student investigates how light intensity affects the rate of photosynthesis in pondweed. The student counts bubbles for 2 minutes at each distance from the lamp. Which improvement would most increase the reliability of the results?

  1. Use a brighter lamp for all distances
  2. Repeat the count at each distance and calculate a mean Correct answer.
  3. Change the temperature between trials
  4. Count the bubbles for only 30 seconds

Explanation

Reliability is improved by repeating measurements under the same conditions and averaging them, which reduces the effect of random variation. Using a brighter lamp or changing the temperature would alter the conditions and could introduce systematic differences. Counting for a shorter time would reduce precision.

Question 39Scientific Processes and Skills

Two students investigate whether a fertiliser increases plant height. Student A uses 30 plants and Student B uses 3 plants, with all other conditions identical. Which statement best explains why Student A's conclusion is more trustworthy?

  1. A larger sample guarantees the hypothesis is correct
  2. A larger sample makes the investigation take less time
  3. A larger sample reduces the influence of natural variation between individual plants Correct answer.
  4. A larger sample removes all sources of error from the experiment

Explanation

Individual plants vary naturally in height, so a larger sample gives a mean that is less affected by unusual individuals and more representative of the population. This improves the reliability of any comparison. A larger sample reduces but never eliminates error, and it cannot guarantee that a hypothesis is true.

Question 40Scientific Processes and Skills

A student's data show that as the concentration of a reactant increases, the time taken for a reaction to finish decreases. The student concludes that increasing concentration slows the reaction. What is wrong with this reasoning?

  1. Time should always be the independent variable
  2. The concentration was not measured accurately enough
  3. The conclusion should not mention the reactant
  4. A shorter time means a faster reaction, so the conclusion contradicts the data Correct answer.

Explanation

The time taken is inversely related to the rate: if the reaction finishes in less time, it is proceeding faster. The data therefore show that increasing concentration speeds up the reaction, so the conclusion reverses the actual trend. Recognising this inverse relationship is essential when interpreting rate data.

Question 41Living Things and the Environment

In an ecosystem, which term describes a green plant that makes its own food using sunlight?

  1. Consumer
  2. Predator
  3. Producer Correct answer.
  4. Decomposer

Explanation

A producer is an organism that builds its own food from simple substances, usually through photosynthesis. Green plants are the main producers in most land ecosystems because they convert sunlight energy into stored chemical energy.

Question 42Living Things and the Environment

Which gas do plants take in from the air and use during photosynthesis?

  1. Nitrogen
  2. Oxygen
  3. Carbon dioxide Correct answer.
  4. Hydrogen

Explanation

During photosynthesis plants absorb carbon dioxide through their leaves and combine it with water using light energy. Oxygen is released as a by-product rather than being the input gas.

Question 43Living Things and the Environment

A rabbit eats grass, and a fox eats the rabbit. In this food chain, what is the fox called?

  1. A decomposer
  2. A secondary consumer Correct answer.
  3. A primary consumer
  4. A producer

Explanation

The grass is the producer, the rabbit is the primary consumer that eats it, and the fox is the secondary consumer that eats the rabbit. Feeding level is counted by how many steps the organism is from the producer.

Question 44Living Things and the Environment

Which of these is an abiotic factor in a pond habitat?

  1. Water temperature Correct answer.
  2. Water lilies
  3. Algae
  4. Tadpoles

Explanation

Abiotic factors are the non-living physical and chemical features of a habitat, such as temperature, light and dissolved oxygen. Living organisms like plants and animals are biotic factors.

Question 45Living Things and the Environment

What is the main source of energy for almost all food chains on Earth?

  1. Wind
  2. The sun Correct answer.
  3. The soil
  4. Rainwater

Explanation

Sunlight supplies the energy that producers capture during photosynthesis, and this energy passes along the food chain. Soil, wind and rainwater provide materials or conditions but not the original energy input.

Question 46Living Things and the Environment

Which human activity most directly destroys the habitat of organisms living on a coral reef?

  1. Releasing untreated sewage into the sea Correct answer.
  2. Collecting rainwater from roofs
  3. Planting trees on a hillside
  4. Building a wind farm inland

Explanation

Untreated sewage adds nutrients and pollutants to seawater, which can smother corals and encourage algae that block sunlight. Coral organisms need clear, clean water, so this activity damages their habitat directly.

Question 47Living Things and the Environment

Which group of organisms recycles nutrients by breaking down dead leaves and animal remains?

  1. Decomposers Correct answer.
  2. Herbivores
  3. Carnivores
  4. Producers

Explanation

Decomposers such as bacteria and fungi break down dead organic matter and release nutrients back into the soil. This recycling keeps minerals available for producers to use again.

Question 48Living Things and the Environment

A population of frogs lives in a marsh that is drained to build houses. What is the most likely immediate result for the frogs?

  1. They will change into a different species
  2. They will lose breeding sites and their numbers will fall Correct answer.
  3. They will start making their own food
  4. Their population will increase because there is more space

Explanation

Draining removes the water and vegetation that frogs need for shelter, breeding and food. Loss of habitat usually causes a population decline because individuals cannot survive or reproduce.

Question 49Living Things and the Environment

In a food web, a hawk eats snakes and mice. Removing all the snakes would most likely cause which change?

  1. The hawk would eat more mice Correct answer.
  2. The hawk would become a producer
  3. The mice would all die out at once
  4. The mice would stop reproducing

Explanation

A predator that loses one prey type often shifts to the remaining prey. With snakes gone, the hawk would probably take more mice, which could reduce the mouse population.

Question 50Living Things and the Environment

Why does energy decrease at each level of a food chain?

  1. Much energy is lost as heat during respiration and life processes Correct answer.
  2. Consumers create new energy by eating
  3. Energy is destroyed completely at each step
  4. Producers absorb energy from consumers

Explanation

Organisms use much of the energy they obtain for movement, growth and other life processes, and some is released as heat. Only a small fraction is stored in the body and passed to the next consumer.