Question

In the buccal cavity of frog, the internal nares are
A) One
B) Two
C) Fused
D) Absent

Answer 1

The buccal cavity and pharynx are shared passageways for the movement of air in and out of the respiratory passage and movement of food and water into the digestive tube.

Complete answer:
Let’s first need to know about these organs.
A. Frog controls its breathing by exciting its throat and breathes with its mouth closed. The association made by the oesophagus pulls oxygen into its body through its nares and into its lungs.
B. Frogs have a couple of internal nares, in the form of small inaugural are situated on the top of the buccal cavity lying outside to vomerine teeth. They have two internal nares one is internal and other one is external nares.
C. Frogs rarely on their lungs to breathe and need more oxygen than only the skin respiration can supply. The lungs serve as the breathing organ. They have a pair of elongated, pink-coloured sac-like structures.
D. Frogs breathe only through the lungs as the air reaches the buccal cavity through the nostrils and then through the lungs. Therefore, until they reach maturity the frog breathes through the lungs.

So, the correct answer is option (B) Two.

Note:
Frogs have an extra breathable surface other than skin-the wet mouth lining. If the mouth of the frog is not fully immersed in water, this respiratory lining is in continuous use, carrying oxygen from the ambient air into the bloodstream and distributing extra carbon dioxide back into the environment.