Which of the following statements are applicable to hormones?
$I -$ Neural messengers
$II -$ Intercellular messengers
$III -$ Produced in trace amounts
$IV -$ Nutrient chemicals
$V -$ Released into the blood after production.

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$: $FSH$,which interacts with membrane-bound receptors,does not enter the target cell.
Reason $(R)$: Binding of $FSH$ to its receptors generates a second messenger (cyclic $AMP$) for its biochemical and physiological responses.
In the light of the above statements,choose the most appropriate answer from the options given below:

The secondary messenger which shows an antagonistic effect to $cAMP$ in heart muscle is

Which of the following is an amino acid derivative?

The word "hormone" means

Which of the following is not necessarily a property of all hormones?