Scientific Method
What is the purpose of conducting multiple trials in an experiment?
To increase reliability of the results
What is the independent variable in an experiment?
The variable that is changed or manipulated
You track the temperature of a greenhouse every hour from 8 AM to 8 PM.
Question: What type of graph is most appropriate for this data?
Line graph
Is “the sun rises in the east” an observation or an inference?
Observation
Why is reproduction important for living organisms?
To pass on genetic material and ensure survival of species
After collecting data on plant growth, you notice the plants with more water grow taller. What should you do next in the scientific method?
Draw a conclusion or communicate results
You measure the height of plants after 2 weeks of fertilizer treatment. What is the dependent variable in this experiment?
Plant height
You are comparing growth rates of two plant species. Which graph type would best display this comparison?
Bar graph
Newton’s law of gravity predicts how objects fall, but the theory of gravity explains why they fall. Which explains the difference between a law and a theory?
Law describes what happens, theory explains why
You observe a single-celled organism moving toward food. Which characteristic of life does this illustrate?
Movement / response to stimuli
Why is it important to have a control group in an experiment?
To compare results and isolate the effect of the variable
In a study testing plant growth with different amounts of fertilizer, what is the independent variable?
Amount of fertilizer
What must always be included on both axes of a graph?
Labels and units
What is a scientific law?
A statement that describes a natural phenomenon consistently observed
A plant grows taller each week. Which characteristic of life does this demonstrate?
Growth and development
What should be done if the data does not support your hypothesis?
Revise the hypothesis or conduct a new experiment
Your friend claims that adding music helps plants grow. You decide to test this. What would be the independent variable?
Whether or not the plants are exposed to music
Your class collects data from 100 students about their favorite fruit.
Question: What type of graph would best show the number of students who chose each fruit?
Pie Chart
How is a scientific theory different from a law?
A theory explains why something happens, a law describes what happens
Name three characteristics all living things share.
Growth, reproduction, response to stimuli (or metabolism, homeostasis, cellular organization)
What does a hypothesis represent in an experiment?
A testable prediction
What is the difference between a control group and a controlled variable?
A control group represents a trial group that does not receive the treatment (independent variable). While, controlled variables are those which are kept the same throughout the test groups to maintain consistency.
You’re showing how the average heart rate changes in response to increasing levels of physical activity (walking, jogging, sprinting).
Question: Which graph type would best show the trend in heart rate?
Line graph
What is an inference?
A logical interpretation based on observations and prior knowledge
Your body regulates blood sugar levels with the production of insulin and glucagon. This is an example of which characteristic of living things?
Homeostasis