Question

Subrostral fossae are-
A) Three terminal over upper jaw
B) Three terminal over lower jaw
C) Two lateral over upper jaw
D) Two lateral over lateral jaw

Answer 1

The word fossa means a ditch. In anatomy, it is a depression in a bone.

Complete Answer:
The subrostral fossae are present in the facial skeleton, behind the upper jaw. Opposite to the subrostral fossae, there are pre-lingual elevations which are three small elevated structures. They are placed at the tip of the lower jaw. During the exchange of gases, these elevations get fixed into the subrostral fossae and help in closing the mouth firmly.

Additional information- an opposable articulated structure present at the entrance of the mouth is called a jaw, it is typically used for grasping and chewing food. The term is broadly applied to the structures constituting the vault of the mouth as a whole. It serves in opening and closing the mouth and is present in humans and most animals. In humans, the upper jaw is called maxilla and lower one is called mandible.
The maxilla is the upper fixed jaw bone. It is formed by the fusion of two maxillary bones. The two bones are joined at the intermaxillary suture, which forms the anterior nasal spine, it has a hard palate in the front of the mouth. This is similar to the lower jaw which is also formed by fusion of two mandibular bones and their place of fusion is called mandibular symphysis. The movable part of a jaw is the mandible.

So the correct answer is- A. Three terminal over upper jaw.

Note: Subrostral fossae are present in the maxillary region of the jaw. They are elevations which help in closing of the mouth smoothly.