The number of active sites in an allosteric enzyme is:

Which of the following units have a shape that is complementary to each other,similar to a lock and key?

Which type of enzymes catalyze the joining of two molecules by utilizing energy derived from the pyrophosphate bond of $ATP$?

Which of the following statements is true regarding enzyme inhibition?

Which one of the following statements is incorrect?

What does $R$ represent in the given figure?