Anatomy and Physiology of the Nose and Throat. External meatus. Triangular shaped projection in the center of the face. External nostrils. Two chambers divided by the septum. Septum. Made up primarily of cartilage and bone and covered by mucous membranes. Nasal passages. Sinuses.. The nasal cavity refers to the interior of the nose, or the structure which opens particles in the air to be trapped before entering other parts of the respiratory system e.g. the lungs ..Nose Parts. The nose has two holes called nostrils. The nostrils and the nasal passages are separated by a wall called the septum say SEP tum . Deep inside your nose, close to your skull, your septum is made of very thin pieces of bone..
