What is the function of the structure labeled $P$ in the given image?

The $Chloragogan$ cells of $Pheretima$ are analogous to which organ in humans?

Spermathecae in earthworm are used for:

Assertion : Typhlosole increases the effective area of absorption in the intestine.
Reason : Typhlosole,present in the intestine,is the characteristic feature of cockroach.

Study the following in $Pheretima$.
$I.$ Dorso-intestinal blood vessels
$II.$ External intestinal plexus
$III.$ Internal intestinal plexus
$IV.$ Ventro-intestinal blood vessel
Arrange the blood vessels in the correct sequence of blood flow from the ventral blood vessel to the dorsal blood vessel.
The correct sequence is:

Identify the correct terms for the following analogy:
$(i)$ Excretory organ in cockroach : Malpighian tubules :: In earthworm : ...........
(ii) Scientific name of cockroach : Periplaneta americana :: Scientific name of earthworm : ...........