The Nose

The nose lets us smell and it's a big part of why we are able to taste things. The nose is also the main opening to the respiratory system, our body's system for breathing. The nose has two holes called nostrils. The nostrils and the nasal passages are separated by a wall called the septum.

Deep inside the nose, close to the skull, the septum is made of very thin pieces of bone. Closer to the tip of the nose, the septum is made of cartilage, which is flexible material that's firmer than skin or muscle. It's not as hard as bone, and if you push on the tip of your nose, you can feel how flexible it is.

Behind the nose, in the middle of the face, is a space called the nasal cavity. It is connected with the back of the throat. The nasal cavity is separated from the inside of the mouth by the palate which is actually the ‘roof' of the mouth. When you inhale air through the nostrils, the air enters the nasal passages and travels into the nasal cavity. The air then passes down the back of the throat into the trachea (or windpipe) on its way to the lungs.

The nose is also a two-way street. When you exhale the old air from your lungs, the nose is the main way for the air to leave the body. But the nose is more than a passageway for air. The nose also warms, moistens, and filters the air before it goes to the lungs.

The inside of the nose is lined with a moist, thin layer of tissue called a ‘mucous membrane'. This membrane warms up the air and moistens it. The mucous membrane makes mucus (snot). Mucus captures dust, germs, and other small particles that could irritate the lungs. Inside the nose, there are also hairs that can trap large particles, like dirt or pollen.

Further back in the nose there are even smaller hairs called cilia that you can see only with a microscope. The cilia move back and forth to move the mucus out of the sinuses and back of the nose. Cilia can also be found lining the air passages, where they help move mucus out of the lungs.