Anatomy of the Nose: What to Know

Medically Reviewed by Mahammad Juber, MD on October 04, 2022
5 min read

Your nose is a vital organ that plays a central role in bodily functions like breathing and smelling. However, there are additional functions that your nose participates in. Likewise, there are a few health conditions regarding the nose to know about, aside from a runny or stuffy nose.

This article details everything you need to know about nose anatomy — the nasal structures that help carry out its functions — and discusses some important disorders for your understanding.

Your nose is the part of your face that projects forward and is a vital part of your respiratory system, among others.  

When looked at from the outside, the nose has a shape similar to that of a pyramid. This shape is known as the external meatus. The top portion of the nose — the nasal root — connects your nose to your forehead. The bottom of the nose is also called the “apex” and is where you find nostril openings. 

Outer structure. The outer part of your nose consists of the nasal bone, cartilage, and fat. Together, they define the shape of your nose and house the nostrils.

Nostrils. The nostrils are the openings to the nasal cavities, allowing air passage. 

Septum. The septum is a combination of bone and cartilage along the center of your nose that divides it into two nasal cavities.

Nasal cavities. Each nostril leads to a nasal cavity. In this part of your nose, breathed-in air is filtered by cilia — hair-like structures inside the nostrils — before entering your lungs. Additionally, each nasal cavity is lined with mucus membranes and respiratory (epithelium) cells.

Mucus membrane. This layer inside each of your nasal cavities warms and moistens the air moving to the lungs.

Turbinate. Turbinates are ridges, or small bony structures, on the inside of your nose. Each nasal cavity contains three turbinates, yielding the mucus that moistens the inside.

Sinuses. Your sinuses are small air pockets on either side of your nasal cavities and are categorized by location on your face:

  • Sphenoid (behind your nose) 
  • Ethmoid (between your eyes) 
  • Frontal (behind your forehead) 
  • Maxillary (behind your cheekbones)

Small muscles are connected to the outside of your nose, which assist with facial expressions. For example, the nasalis muscles are a part of your nostrils, allowing you to flare them. Research suggests that the muscles inside your nose also play an essential role in facial expression and airflow. 

It’s worth noting that your nose does not function separately from other parts of your body, such as your ears and throat. For example, experiencing a sinus infection may also lead to a sore throat. 

Three functions of the nose include respiration, defense against dirt and other particles, and sense of smell.

Respiration. When you breathe, the air enters the nasal cavities and comes in contact with the mucus membranes, which warms the air’s temperature to a more suited degree for your lungs. From the nasal cavity, the air moves down the trachea, commonly known as the “windpipe,” and down to your lungs. There, the lungs pass oxygen into your bloodstream in exchange for carbon dioxide, which you then breathe out through your nose. 

Defense mechanism. Your nasal cavity is a part of your body’s defense mechanism against allergens and external particles that may enter as you breathe. The mucus membrane in the nasal cavity traps these potentially harmful particles.

Sense of smell. Your sense of smell is medically known as the olfactory system. This function allows you to identify fragrances and alerts you to potentially dangerous situations. The olfactory receptors in the nasal cavity send signals to your brain, which interprets the information.

Your nose projects from the center of your face. The internal structures of your nose are above the roof of your mouth.

Like any other bone, pain, swelling, and tenderness around your nose may indicate that it’s broken. Other signs of a broken nose include bruising, difficulty breathing, and a feeling that one or both nasal cavities are blocked.

You may experience other signs and symptoms that indicate a problem beyond a broken nose. Some symptoms are mild and may just mean you have a cold, such as allergic rhinitis. Also known as hay fever, this condition can cause irritation, runny or stuffy nose, and constant sneezing.

However, other signs may point to a more serious problem, such as a sinus infection. Signs to watch out for and may mean seeking medical help include:

  • Nosebleeds
  • Headaches with facial pain
  • Yellow or green mucus production
  • Loss of smell or taste
  • Bad breath

Several health disorders can affect normal nose functions. Sometimes, a runny or stuffy nose simply means you have a cold, but other nasal conditions need more serious attention. 

Deviated septum. In this condition, the septum falls away from the center and impacts regular nose functions. A deviated septum could lead to breathing difficulties, snoring, loud breathing, nosebleeds, and frequent sinus infections. Sometimes, it may also affect your sense of smell and taste. You can have a deviated septum treated with surgery.

Nasal polyps. The formation of lumps, or polyps, in the nasal cavities block the air passage and makes it difficult for you to breathe normally. Some people who often experience nasal or sinus irritations may be at risk of developing nasal polyps.

Turbinate conditions. As one of the types of chronic nasal obstruction, your turbinate may have excess tissue. Of course, this leads to difficulty breathing and may require surgery to alleviate the blockage.

Cancer. Nasopharyngeal cancer is found inside your nose and typically originates in the upper part of your throat and behind your nose. Nasopharyngeal cancer leads to difficulty with breathing, speaking, or hearing. Although classified as a type of head and neck cancer, it impacts nasal functions.

Although there are many conditions that involve and affect your nose, you can take precautions to maintain your nose health.

  • Avoid plucking your nose hairs, as they are essential in filtering out dust and allergens from the air. 
  • Stay hydrated to help retain moisture in your nasal cavities. 
  • Consider quitting smoking and keeping away from secondhand smoke.
  • Keep your nasal cavities clean by gently spraying saline water into them regularly.
  • Seek medical help if you experience spontaneous nosebleeds. They aren’t usually concerning and tend to stop on their own, but you may wish to find out the cause if they happen frequently.