Which type of DNA mutation is the result of a new nitrogenous base being added to a DNA strand

What is one function of the embedded proteins

Actinobacteria sp. are fermenting organisms (which do you use oxygen to breathe) referred to as chemoorganohetereotrophs this means they break down organic material and convert it to inorganic material. which part of the carbon cycle does this describe

What organ is the first to receive nutrients that have been absorbed from the digestive tract?