The immune system has many kinds of white blood cells to fight infections. HIV finds the white blood cells, called CD4 cells. But with cancer the white blood cells are being killed off.
In an experiment, the respiration rate of a goldfish is measured by placing the goldfish in cold water and then the respiration rate is measured again, the cold water is the independent variable.
<h3>What is an independent variable?</h3>
Independent variable is the variable of an experiment that is manipulated or changed while the dependent variable is the variable that is measured or recorded in an experiment.
According to this question, the respiration rate of a goldfish is measured. The goldfish is placed in cold water and then the respiration rate is measured again.
The cold water is the independent variable because it is the variable that is changed in terms of temperature difference.
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