An absorptive heterotroph is an organism which secretes enzymes externally into its environment to digest organic materials which are then absorbed.
This was answered else where on Brainly, and this is what they said,
"Most proteins in the living organisms are enzymes and they required specific optimum conditions in order to function optimally. Disruption in the homeostasis will leads to deactivation of these proteins. For instance, if the temperature needed for a protein to work optimally has been exceeded, the protein may be denatured and will be unable to perform its needed functions, this may result in several adverse effects in the organism."
The aqueous bromothymol blue solution act as a pH indicator and turns blue only in case when the pH of the sample is above or equal to 7.6
Since the pH of the water at the surface of the lakes is higher and ranges between 7.5 to 8.5 the color of bromothymol turn blue.
