Scientific Method
Experimental Data Interpretation
Observations, Inferences
What makes something living?
Science?
100
Testing hypotheses often involves designing experiments. Which of the following is the factor that is observed and measured in an experiment?
a. control group
b. experimental group
c. dependent variable
d. independent variable
c. dependent variable
100
An osmosis investigation was conducted using chicken eggs to represent cells with semipermeable membranes. The mass of each egg was measured to determine how much water diffused into or out of the eggs. The eggs were first soaked in vinegar to dissolve the shell. Each egg was then placed in one of three different solutions for 24 hours. The table below shows the results of the investigation.
Based on this experiment, which of the following should be inferred about cells with semipermeable membranes? (HINT: Pay attention to the water concentrations!)
A. Substances other than water may also cross the cell membrane.
B. Substances other than water may block pores in the cell membrane.
C. Water enters the cell when placed in environments of high water concentration.
D. Water leaves the cell when placed in environments with a low concentration of solutes
C. Water enters the cell when placed in environments of high water concentration.
In both the vinegar (95% water) and distilled water (100% water) solutions, the egg gained mass after soaking. This means that water moved into the egg over time. The reason for this movement is that the solutions are both hypotonic to the concentration of the egg. Water always moves from a more hypotonic solution to a more hypertonic solution (which has more solutes and less water).
This item also assesses your ability to read and interpret graphs, charts and data tables. Even if you had no knowledge of hypo and hypertonic solutions, you could use the data in the table to conclude that in the solutions with the most water, the eggs gained the most mass.
100
Mrs. Manasco loves all animals.
Is this statement an observation or an inference?
Inference
100
Which characteristic of life is missing from this list?
1. Evolve
2. Use Materials and Energy
3. Based on a Universal Genetic Code
4. Grow and Develop
5. Reproduce
6. Respond to their environment
7. Maintain Homeostasis
8?
Made up of cells
100
Dr. Smith reads two research papers that present different conclusions about the same question. He knows the researcher who wrote Paper A, but does not know the authors of Paper B. When asked which paper he thinks has more merit, Dr. Smith replies, “Paper A.”
Because of Dr. Smith's personal connection to some of the researchers, he could be exhibiting
a. bias.
b. inference.
c. observation.
d. skepticism.
a. bias.
200
Dr. Sanchez and her team have observed an unusual star in the Andromeda galaxy. Their data suggests that the star is being consumed by a nearby black hole. They write a scientific paper about their work and submit it to a scientific journal. Other scientists read their paper and look for the unusual star as well.
The other scientists are participating in which activity?
a. data collection
b. peer review
c. developing a hypothesis
d. developing a theory
b. peer review
200
The graph below shows atmospheric carbon dioxide levels since the year 1880.
Which of the following conclusions can be drawn from this graph?
A. Atmospheric carbon dioxide levels are responsible for global temperature change.
B. Atmospheric carbon dioxide levels have been rising at about the same rate for the past century.
C. Atmospheric carbon dioxide levels have remained the same over the past century.
D. Atmospheric carbon dioxide levels have been rising at an increasingly higher rate as the past century has progressed
D. Atmospheric carbon dioxide levels have been rising at an increasingly higher rate as the past century has progressed.
Because the graph shows a curved line, instead of a straight one, you can conclude that as time has passed (on the x axis) the levels of atmospheric carbon dioxide (on the y axis) have risen at increasingly higher rates. If levels had increased at the same rate, the line would be diagonal from left to right, but it would be straight.
200
What is an inference?
a. Just a guess.
b. A conclusion/statement based off of your observations and past experiences.
c. The same as an observation.
d. Examples of something.
b. A conclusion/statement based off of your observations and past experiences.
200
The process by which organisms keep their internal conditions relatively stable is called
a. metabolism
b. a genome
c. evolution
d. homeostasis
d. homeostasis
200
Much evidence has been discovered to support biological theories such as cell theory and germ theory, and no evidence has been found to prove these theories incorrect. Which statements are true about theories in general? Select two answer choices.
a. Theories may become scientific law.
b. Theories are broad and useful explanations for how the world works.
c. Theories are accepted as absolute truth in the scientific community.
d. Theories are dynamic and complex, and are constantly subject to revision.
b. Theories are broad and useful explanations for how the world works.
d. Theories are dynamic and complex, and are constantly subject to revision.
300
Carmen conducted an experiment to determine if listening to different types of music would affect a person’s pulse. Her hypothesis was that pulse rate would change with different types of music. Each person listened to seven different selections of music for 30 seconds each. Each person’s pulse was taken before the music and then after each 30-second interval of music. The pulses were taken again after the music selections were completed. Based on her experiment, Carmen concluded that a person’s pulse rate changed when the person listened to different types of music.
Which component is missing from Carmen’s experiment?
A. a question
B. a hypothesis
C. a control group
D. a description of the experiment
C. The experiment is lacking a control group.
Carmen should have also taken the pulse of people who were NOT listening to any music to make sure that a person’s pulse rate would not change randomly.
300
A scientist performs an experiment to see if acids have an effect on the health of a particular type of plant. Three sets of plants were treated with acidic solutions of known pH while the control set was treated with a solution of neutral pH 7. (High Acidity= pH 0-6)
Which is the best conclusion for this experiment? A. Acid has no effect on the health of this type of plant. B. High acidity is helpful to this type of plant. C. Low acidity is harmful to this type of plant. D. High acidity is harmful to this type of plant.
D. High acidity is harmful to this type of plant.
Plants in the lowest pH (highest acidity) group were adversely affected the most.
300
Jane Goodall spent years with the chimpanzees of Gombe. Sitting quietly for hours, she watched the animals closely and took notes about their behavior.
What was Jane Goodall doing?
a. testing variables
b. watching a control group
c. making observations
d. applying a stimulus
c. making observations
300
After her run, Aisha felt thirsty. Thirst was her body’s way of telling her she needed more water to maintain
a. growth.
b. metabolism.
c. development.
d. homeostasis.
d. homeostasis.
300
Tamar is talking about evolution with a friend. The friend says, “It’s just a theory, so I don’t believe it. When they prove it and it becomes the law of evolution, then maybe I’ll change my mind.”
Which of these possible replies best describes scientific principles or the work of scientists?
a. Scientific theories do not become scientific laws; they are explanations for natural phenomena based on evidence.
b. Science always finds the right answer; the answers that scientists and researchers discover never change.
c. He should be wary of science because it is based on research and evidence, not bias and opinion.
d. Scientists take each other at their word regarding experimental results, and the public should, too.
a. Scientific theories do not become scientific laws; they are explanations for natural phenomena based on evidence.
400
Michael’s grandmother is taking part in an experiment to determine how well a new headache medication works. In this experiment, the people in Group A are taking the new medication. The people in Group B, including Michael’s grandmother, are taking a pill that does not contain the new medication.
In this experiment, what is Group B?
a. Group B is the control group.
b. Group B is the experimental group.
c. Group B is the independent variable.
d. Group B is the dependent variable.
a. Group B is the control group.
400
A research group has discovered that damselflies, a type of dragonfly, are being infected by a particular type of aquatic protozoan. Both young and adult damselflies are not directly infected by the protozoan but contract the infection from the prey they eat. The graph shows the percentage of adult damselflies infected by protozoans during the summer and early fall.
Which of the following conclusions is supported by the graph?
A. Infection in embanked ponds increased during the sampling period.
B. Protozoans were more common in creek-fed ponds than embanked ponds.
C. Protozoans reproduce more quickly in embanked ponds than creek-fed ponds.
D. Infection in creed-fed ponds remained constant throughout the sampling period.
A. Infection in embanked ponds increased during the sampling period.
The percent infected continually rose for these ponds as time progressed. D is incorrect is because although the readings present on the graph are all relatively similar, there are no readings (or no infections) on some of the dates.
400
Camille notices that the leaves of her pothos plant are drooping this morning. The leaves were not droopy yesterday. She decides the plant needs to be watered. What had Camille just done?
a. calculated the probability of the plant’s ability to survive without water
b. devised a controlled experiment about the effect of water on plant leaves
c. formed a hypothesis based on quantitative data she has collected
d. made an inference based on past experience and observation
d. made an inference based on past experience and observation
400
Scientists’ understanding of viruses has advanced greatly in the last fifty years. Which two statements provide evidence to support viruses being best classified as nonliving? Select two answer choices.
a. Viruses are made up of proteins, nucleic acids, and sometimes lipids.
b. Viruses do not respond to changes in the environment around them.
c. Viruses contain genetic information in the form of nucleic acids.
d. Viruses must infect living cells in order to reproduce.
b. Viruses do not respond to changes in the environment around them.
d. Viruses must infect living cells in order to reproduce.
400
Science began out of humankind’s natural curiosity to understand and explain the interactions and processes of the natural world. Science aims to use these explanations to understand patterns in nature and benefit nature and society, as well as to address issues that face the natural world and human society.
Which statement BEST reflects the efforts of scientists in pursuing the goals of science?
a. Scientists make observations and conduct experiments in order to establish facts.
b. Scientists attempt to resolve questions of belief with scientific facts.
c. Scientists review and revise current knowledge when new evidence arises.
d. Scientists emphasize data that support their hypotheses and ignore data that does not.
c. Scientists review and revise current knowledge when new evidence arises.