1 A small 3-ounce piece of meat has about 21 grams of protein. A typical 8-ounce piece of meat could have over 50 grams of protein. 2  One 8-ounce container of yogurt has about 11 grams of protein. 3  One cup of milk has 8 grams of protein.  One cup of dry beans has about 16 grams of protein.
All of these aspects of peanut growth can be measured and can be used as dependent variables in an experiment. There are different dependent variables possible in an experiment. The investigator can choose the one he thinks is most important, or he can choose to measure more than one dependent variable.
The experiment is a research method in which the investigator manipulates one or more factors to observe their effect on some behavior or mental process, while controlling other relevant factors. If a behavior changes when we vary an experimental factor, then we know the factor is having a causal effect.