Question

Dorsal surface of the nasal chamber is made up of which of the following bones?
A) Nasal
B) Ethmoid
C) Maxilla
D) Vomer

Answer 1

Hint: The upper side or the back portion of an organism is considered as the dorsal surface. Like in the skull the dorsal part is the top. The back of the body is the dorsal part.

Complete answer:
To solve this question, we must first know about the nasal cavity. The nasal cavity is an air-filled space that is found behind the nose in the middle of the face. It consists of septum that divides the cavity into two different cavities that are termed as fossae. The cavity is divided into dorsal, caudal, and ventral. The caudal portion means part away from the head, ventral means the front part of the nose, and the dorsal is the back or upper side of the nose.
Now lets us find the solution from the given options:
Nasal part is the respiratory and olfactory organ. It has a nasal cavity and nasal skeleton. The nasal cavity traps and removes pathogens to enter the respiratory tract, involving in sense the smell, drains the lacrimal ducts and paranasal sinuses.
Next, ethmoid bone is an unpaired bone. This bone separates the nasal cavity from the brain. It is found in the roof of the nose between the orbits. Therefore, this bone is marked as a caudal surface.
Maxilla bone is involved in the formation of the upper jaw. It helps in the formation of the roof of the mouth, form the orbit, and lateral walls of the cavity. It is found in the upper portion or back, therefore, it is the dorsal surface.
Lastly the vomer bone, this is the unpaired facial bone that is found in the midsagittal line. This bone articulates with ethmoid, sphenoid, left and right maxillary bones and palatine bones.

Thus, the right answer is option C. i.e., Maxilla.

Note: The ventral surface is the lower portion or the front portion of the human body. It includes the abdomen, shins, chest, palm, and soles. The caudal surface is the portion away from the head. It involves feet that are in inferior extremity.