Which of the following hormones is derived from an amino acid?

Which one of the following is $NOT$ a second messenger?

Chemically,hormones are ....

Which hormone's mechanism of action is shown in the given diagram?

$A$ molecule that binds to a receptor and induces post-receptor events in a cell is called ...$A$... and a molecule that binds to the receptor and inhibits all post-receptor events is called ...$B$....

Steroid hormones work as: