Chapter 1 Test Review

You do an experiment to see if fertilizer makes plants grow. Which of the following is the dependent variable?

• plant growth

• fertilizer

• sunlight

• soil

Answer explanation

In this experiment, plant growth is the dependent variable because it is the outcome being measured to see if it changes with the application of fertilizer, which is the independent variable.

You notice that your dog is shedding. Which of the following represents a hypothesis about your observation?

• My dog is shedding.

• I wonder why my dog is shedding.

• The weather must be getting warmer.

• My dog pants when she is warm.

Answer explanation

The statement 'The weather must be getting warmer' is a hypothesis as it suggests a possible explanation for the observation of shedding, linking it to a change in weather, unlike the other options which are observations or questions.

For her science project, a student collects data on deer spotted in a field each day. For the first five days of her study, she counted 23, 16, 18, 27, and 19 deer. What type of observation do these data represent?

• an inferred observation

• a quantitative observation

• a qualitative observation

• a classified observation

Answer explanation

The data collected represents counts of deer, which are numerical values. This makes the observations quantitative, as they involve measuring quantities rather than describing qualities.

Explaining or interpreting the things you observe based on reasoning from what you already know is called

• observing

• inferring

• predicting

• classifying

Answer explanation

Inferring involves explaining or interpreting observations based on prior knowledge and reasoning. This distinguishes it from observing (noting details), predicting (forecasting future events), and classifying (grouping items).

If you conduct an experiment and draw conclusions that are based on your beliefs rather than the facts, you are using

• objective reasoning.

• deductive reasoning.

• inductive reasoning

• subjective reasoning

Answer explanation

When conclusions are drawn based on beliefs rather than facts, it reflects subjective reasoning. This contrasts with objective reasoning, which relies on factual evidence.

Which is an example of using ethics in experiments?

• making sure other scientists can repeat the experiment

• taking care that no animals are harmed

• storing samples under controlled conditions

• making sure that only useful data are collected

Answer explanation

Taking care that no animals are harmed is a clear example of ethics in experiments, as it reflects the responsibility to ensure the welfare of living subjects involved in research.

Observations that deal with descriptions that cannot be expressed in numbers are called

• A. relative observations.

• B. quantitative observations.

• C. qualitative observations.

• D. evidence observations.

Answer explanation

Observations that cannot be expressed in numbers are known as qualitative observations. They focus on characteristics and descriptions rather than numerical data, making option C the correct choice.

Trying to explain why a solar eclipse occurs is an example of

• A. a prediction.

• B. an experiment.

• C. scientific inquiry.

• D. classification.

Answer explanation

Explaining why a solar eclipse occurs involves asking questions and seeking answers through observation and reasoning, which is the essence of scientific inquiry. Thus, the correct choice is C.

Scientific knowledge changes with

• A. new magazine articles.

• B. careful reading of facts.

• C. repeated experiments.

• D. new evidence or new interpretations.

Answer explanation

Scientific knowledge evolves primarily through new evidence or interpretations, as these can lead to revised theories and understandings. Thus, option D is the correct choice.

possible explanation for a set of observations or possible answer to a scientific question

• dependent variable

• controlled experiment

• independent variable

• hypothesis

Answer explanation

A hypothesis is a proposed explanation for a set of observations or a potential answer to a scientific question. It serves as a starting point for further investigation and testing.