Chemically,hormones are composed of ........

Which row in the chart contains the words that best complete this statement? The $(I)$ glands produce $(II)$, which are transported by the $(III)$ system.

Row	$I, II, III$
$A$. digestive, hormones, circulatory
$B$. endocrine, enzymes, lymphatic
$C$. endocrine, hormones, circulatory
$D$. digestive, enzymes, lymphatic

$A$ 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 ...$B$....

According to the mechanism of hormone action,if the receptor molecule is removed from the target organ,the target organ will:

Which of the following hormones never enters the cytoplasm of the target cell?

Which of the following is not a secondary messenger?