The opening of the rectum in frogs is termed as:

Frogs live in or near water because .....

Bidder's canal is found in

Choose the correct sentences for a female frog.
$1$. Vocal sacs are absent in female frogs.
$2$. $A$ mature female can lay $2500$ to $3000$ ova at a time.
$3$. In female frogs,fertilized eggs are encased in oothecae and it is a dark reddish to blackish brown.

Mesorchium in frog refers to

Describe the circulatory system of a frog.