Difference Between Alveoli and Bronchi (With Table)

The pounding of our hearts and the rise and fall of our chests indicate that we are alive. In reality, we require air to survive. With the assistance of our respiratory system, we can breathe in. Have you ever thought about how we relax? The lungs anticipate becoming the most enjoyable aspect of our relaxation.

We wouldn’t be able to relax if part of our body’s critical respiratory plans, such as the alveoli and bronchi, were missing. Almost certainly, you’ve known about the alveoli and bronchi since elementary school. These topics, on the other hand, were only skimmed over. Allow us to demonstrate the crucial distinction between alveoli and bronchi.

Alveoli vs Bronchi

The main difference between alveoli and bronchi is that alveoli participate in gas exchange, whereas bronchi serve as a link between the windpipe and the lungs. The respiratory system relies on the two alveoli and bronchi. The lungs are made up of bronchi, bronchi, and alveoli.

Alveoli, the plural form of the word “alveolus” is alveoli. Consider a picture of the lungs. There’s almost nothing at the tip of our lungs, with bronchi branching out in all directions. Furthermore, we can see small air sacs at the tip of our bronchi. The alveoli are the air sacs in the lungs. The carbon dioxide and oxygen exchange is the tremendous limit of these tiny air sacs.

Bronchi is a bronchus that connects our windpipe to our lungs and is shown as a giant chamber. The bronchial chambers are then outlined in a more inconspicuous manner. Our bronchi are crucial for bringing air into our lungs and for bringing air out of our lungs.

Comparison Table between Alveoli and Bronchi

Parameters Of ComparisonAlveoliBronchi
DefinitionThe any of the tiny air sacs of lungsThe tiny branches of air tubes within the lung.
ShapeSac-like structureSac-like structure
DivisionsAlveolar sacsBronchioles
Starting PointLung parenchymaCarina is the point
where the windpipe detaches into bronchi.
FunctionExchanges gasesCarries gases.

What is Alveoli ?

After the respiratory aeronautics courses, alveoli are the numerous tiny air sacs of the lungs, further separated as alveolar sacs. The alveoli in the mammalian respiratory system are referred to as pneumonic alveoli. The distance across the sac of alveoli is typically 0.2-0.5 mm. Alveoli together resemble a bunch of grapes.

In a few human lungs, the full-scale conventional surface area of alveoli is roughly 70 m3. As a fundamental squamous epithelium, the respiratory film of the alveoli is also included. Furthermore, the typical limit of alveoli is to work with respiratory gas exchange. De-oxygenated blood travels from the right ventricle of the heart to the lungs via the pneumonic inventory route.

This blood transports carbon dioxide into the alveoli while taking oxygen from the air inside the alveoli. This creates oxygenated blood, which returns to the heart’s left office via pneumonic veins.

What is Bronchi ?

Bronchi are little sections of the respiratory air course, and bronchioles are further split into individual alveoli. Normally, each lung contains roughly 30,000 bronchi. They don’t, however, have tendon rings to enclose the chamber. Smooth muscles, flexible connective tissue, and direct cuboidal epithelium with flask cells make up bronchi.

In addition, the respiratory flying courses include three bronchi. Lobular bronchi, terminal bronchi, and respiratory bronchi are the three types. Furthermore, lobular bronchi, also known as preterminal bronchi, branch off from the tertiary bronchi to form terminal bronchi that lead to an aspiratory lobule. Although terminal bronchi are comprised of fundamental cuboidal epithelium, challis cells are required.

They also develop the respiratory bronchi, which contain non-ciliated cells and lead to alveoli and are suitable for gas exchange. The bronchi’s two major functions, in terms of limitations, are to carry air to alveoli via both lobular and terminal bronchi and to undergo gas exchange.

Main Difference Between Alveoli and Bronchi

  1. There are further divides in considerations, such as lobar bronchi and bronchioles. In any event, the alveoli have recently developed a pack blueprint known as the alveolar sac, which takes place in the acini.
  2. The alveoli have a varied condition that resembles that of a sac or a cup. A bunch of grapes or raspberries are arranged in the alveolar sac. By and large, the bronchi appear to be a chamber, and it is not flexible. The state of an adjusted tree is developed by the complete bronchial divisions working together.
  3. Pneumocytes and pneumonocytes are found in the alveoli. Respiratory epithelial cells line the bronchi, which also contain ligaments, mucous layers, and smooth muscles.
  4. In terms of boundaries, the alveoli carry out vaporous commerce, whereas the bronchi carry out gaseous trade.
  5. The alveoli are little air sacs found near the completion of the bronchioles, while the bronchi begin around the fifth thoracic vertebra.


Bronchi are small tubules of the lungs that interact with respiratory air courses to reach the alveoli. It’s also a part of the lungs’ respiratory zone, with a direct ciliated cuboidal epithelium.

Alveoli, on the other hand, are the little air sacs that surround the bronchioles’ completion. They are also a part of the respiratory system. This massive number of respiratory zones has a large amount of vascularization. As a result, the primary distinction between bronchioles and alveoli is their life structures.


  1. https://www.atsjournals.org/doi/abs/10.1165/rcmb.2005-0180OC
  2. https://www.atsjournals.org/doi/pdf/10.1164/arrd.1979.120.1.151