Lung bud

Definition

The lung bud is a structure that forms early in embryonic development, which eventually gives rise to the major components of the respiratory system such as the trachea, bronchi, and lungs. It appears as a protrusion from the ventral wall of the foregut during the fourth week of human development.

Related terms

Foregut:

The anterior part of the embryonic digestive tube, which gives rise to structures including the pharynx, esophagus, and stomach.

Bronchi:

The major air passages of the lungs that diverge from the windpipe (trachea), providing a pathway for air to reach the lungs.

Alveoli:

Tiny air sacs within the lungs where gas exchange between air and blood takes place