1. Which is not a part of the respiratory system? Alveoli, Lungs, Trachea,
Esophagus

Esophagus

Explanation: The Esophagus is part of the Digestive system and the rest are a part of the Respiratory system.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products