The opening of the rectum in frogs is termed as:

The skull of a frog is . . . . . . .

The $8^{th}$ vertebra of a frog is:

Select the incorrect statement regarding frogs.

Select the correct option regarding the respiratory system of a frog:
$(1)$ The glottis is covered by a thin,elastic cartilaginous flap called the epiglottis.
$(2)$ Frogs respire through gills or moist skin.

In frogs,which system$(s)$ open into the cloaca?