Answer:
The chemical basis of Chargaff"s rule is the bonding properties of  the DNA bases.
Explanation:
According to the Chargaff"s rule in a DNA molecule the total number of purine bases are equal with the total number of pyrimidine bases  that means 
    Adenine +Guanine=Thymine +Cytosine
In simple words the rule is based on the 1:1 ratio of both purine and pyrimidine bases.
 
        
             
        
        
        
First question: “Every system in the body relies on oxygen. From cognition to digestion, effective breathing can not only provide you with a greater sense of mental clarity, it can also help you sleep better, digest food more efficiently, improve your body's immune response, and reduce stress levels.” -google
        
             
        
        
        
As described above, the condition will lead or cause the lung tissue to be less elastic. That being said, the lungs will be limited due to its stiffness. This will lead to decreased lung capacity as well as decreased vital capacity. 
        
             
        
        
        
Answer:
Decomposition occurs through two primary chemical processes: autolysis and putrefaction. They often occur in tandem, but one may predominate in certain conditions. Autolysis (or “self-digestion”) is the destruction of cells through the action of their own enzymes.
Explanation:
 
        
                    
             
        
        
        
The answer is B. Heterotrophs. All animals and fungi are heterotrophs. Hope I helped!