A controlled experiment is one thata. proceeds slowly enough that a scientist can make careful records of the results.b. tests experimental and control groups in parallel.c. is repeated many times to make sure the results are accurate.d. keeps all variables constant.

The best method for determining whether bean plants require sodium is to __________.

A team of scientists has devised a new chemical fertilizer that its members believe will increase crop yields. The team planted three garden plots with corn. The soil was similar in each, and equal amounts of water were applied to each plot. One plot was treated with a common commercial fertilizer, another was treated with the new fertilizer, and the third plot was not given any fertilizer. The experimenters measured yields as bushels of corn from each plot. The plot that did not receive fertilizer was the __________.

Add labels to the figure that follows, which illustrates the characteristics of research participants in control versus experimental groups.

What does it mean to say that experimental conditions are controlled? Select True or False for each statement.T/F The test groups consist of the same individuals.T/F The null hypothesis is correct.T/F There is no difference in outcome between the control and experimental treatment.T/F All physical conditions except for one are identical for all groups tested.

A controlled experiment is one thata. proceeds slowly enough that a scientist can make careful records of the results.b. keeps all variables constant.c. is repeated many times to make sure the results are accurate.d. tests experimental and control groups in parallel.

Control subjects in an experiment .a. should be similar in most ways to the experimental subjects;b. should not know whether they are in the control or experimental group;c. should have essentially the same interactions with the researchers as the experimental subjects;d. help eliminate alternative hypotheses that could explain experimental results;e. all of the above

An experiment in which neither the participants in the experiment nor the technicians collecting the data know which individuals are in the experimental group and which ones are in the control group is known as .a. controlled;b. biased;c. double-blind;d. falsifiable;e. unpredictable

A relationship between two factors, for instance, between outside temperature and the number of people with active colds in a population, is known as a(n) a. a. significant result;b. correlation;c. hypothesis;d. alternative hypothesis;e. experimental test