air cell
Noun: A very small, thin-walled cavity or pouch, especially in the lungs of birds or the respiratory system of some insects, that holds air and is involved in the process of gas exchange. It is formed by the terminal enlargement of tiny air passageways.
The term "air cell" is used specifically in biological and anatomical contexts to describe a structural unit for air containment within an organism's respiratory system. * In birds, the respiratory system includes air cells that extend into bones, making the skeleton lighter for flight. * The efficiency of gas exchange in the lungs depends on the vast number of microscopic air cells.
- The honeybee's tracheal system terminates in small air cells that deliver oxygen directly to tissues.
- During the examination, the veterinarian noted the health of the bird's pulmonary air cells.
- A rupture in one of the air cells can lead to respiratory complications.
- Botany: In some plant tissues, an "air cell" can refer to an intercellular space filled with air, aiding in buoyancy or gas diffusion.
- Food Science: In egg anatomy, the "air cell" is the pocket of air at the blunt end, which enlarges as the egg ages.
- Alveolus (noun): The precise medical and anatomical term for the tiny air sacs in mammalian lungs where gas exchange occurs. An alveolus is a specific type of air cell.
- Air Sac (noun): A broader term for any of the larger, thin-walled structures in the respiratory systems of birds and some reptiles, often connected to air cells.
- Air sac
- Alveolus (in mammalian contexts)
- Vesicle (in some general biological contexts)
The core meaning is a microscopic cavity for holding air. The specific function and location define the type: 1. Respiratory Air Cell: Found in lungs or tracheal systems for gas exchange (e.g., in birds, insects). 2. Egg Air Cell: A specific structure in avian eggs, not involved in respiration but in gas exchange through the shell.
- a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways