When two comparisons groups within an experiment are identical except for one variable the experiment is called

Controlled experiment

Explanation:

A controlled experiment is a type of experimentation that is done under controlled conditions. The procedure entails changing or manipulating one (sometimes more than one) variable or factor at a time, but keeping everything else the same between the groups.

This is done to ensure that the factor or variable they are testing is what elicits any changes in the subject. One group is always kept in normal or standard conditions, to serve as a base line to compare to.  

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

answer: glucoamylase presented optimum activity at temperature of 55â°c, and, in the glycosidic bonds from the non-reducing ends of starch, resulting in the production of glucose. source and type of fermentation can affect the enzyme's properties

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