Which is true about the interaction between the upper respiratory system and respiration?
the lower respiratory tract brings air to the upper respiratory tract so that gas exchange can occur in the nose.
the upper respiratory tract brings air to the lower respiratory tract so that gas exchange can occur in the lungs.
the upper respiratory tract does not play a role in respiration.
all respiration occurs in the upper respiratory tract.

The upper respiratory tract brings air to the lower respiratory tract so that gas exchange can occur in the lungs.

Option b

Explanation:

The respiratory system of the human beings is divided into two parts: The upper part of the respiratory system bring the air inside the body through the nasal passage.

The lower part of the respiratory system helps in the exchange of the gases in the lungs. Here, the carbon dioxide is pushed to exhale and the oxygen is distributed to the various parts of the body along with the blood.

The correct answer out of the four provided options is given by

option C). may change the substrate specificity of the enzyme.

Explanation:

This can be explained as substitution of a single amino acid in the active site of an enzyme will result in the alteration of activity in a protein as this substitution, in fact, has an affect on the assembly, folding or activity. An active site aids to bind the substrate to the enzyme. In case, it gets altered the specificity of the enzyme will be lost to a substrate and hence efficiency will be affected too