What is the primary role of allosteric effectors in enzyme regulation?

Which of the following statements correctly differentiates heterotrophic and homotrophic allosteric effectors?

An enzyme is regulated by an allosteric effector that stabilizes the R state. What type of effector is this, and what is its likely impact on enzyme activity?

An enzyme's sigmoidal curve shifts to the right in the presence of a certain effector. What can be inferred about this effector?

Which of the following correctly describes the roles of ATP and CTP on ATCase?

If a substrate concentration is increased in the presence of an allosteric inhibitor, what is the expected change in enzyme activity?

Which of the following is an example of a homotrophic effector?