It is also found in groundwater
Protein plays a crucial role in almost all biological processes and amino acids are the building blocks of it. A large proportion of our cells, muscles and tissue is made up of amino acids, meaning they carry out many important bodily functions, such as giving cells their structure
Insulin released to prevent the surge of sugar in bloodstream when glucose increases.
The control is the group of no fertilizers.
A control in an experiment is usually the group without the variable to be tested. In this case, the farmer wanted to test the effects of fertilizers, therofre the group without it is the control group.