Bronchium is a term used in anatomy and biology to refer to a structure known as a bronchus. A bronchus is one of the major air passages in the respiratory system of higher mammals, including humans. It functions as a tube or a branch that carries air into and out of the lungs.
Specifically, a bronchium is a tubular structure that begins at the trachea and extends into the lungs, where it continues to divide into smaller and smaller branches, known as bronchioles. These bronchioles eventually lead to the air sacs called alveoli, which are responsible for gas exchange within the lungs.
The bronchium is made up of a combination of smooth and cartilaginous tissues. The cartilage provides structural support, preventing the airways from collapsing, while the smooth muscles allow for the contraction and expansion required for breathing.
The bronchium plays a vital role in respiration by providing a pathway for air to enter and exit the lungs. As air is inhaled, it passes through the trachea and into the bronchium, which subsequently branches out into the bronchioles. From there, the oxygen in the air diffuses into the bloodstream, while carbon dioxide, a waste product, travels in the opposite direction and is exhaled.
In summary, a bronchium is a major air passage that connects the trachea to the lungs, facilitating the exchange of gases during respiration.
