Tracheole
Encyclopedia
Tracheole is a fine respiratory tube of the trachea
of an insect
, part of the respiratory system
.
Tracheoles are about 1µm in diameter, and they convey oxygen to cells while providing a means for carbon dioxide to escape.
Tracheoles branch from the larger tracheae (which can be several mm in diameter) much like capillaries branch from arteries, or twigs from branches of a tree. This increases the surface area for gas exchange in the insect. Areas of intense metabolic activity, such as the digestive tract and flight muscles have very dense aggregations of tracheoles.
Though usually closely associated with cells, tracheoles physically penetrate only the flight muscle cells which have the highest oxygen demands.
Unlike the larger tracheae which are derived of ectodermal stem cells, tracheoles do not molt with the insect. Instead, they remain in place and fuse themselves to new tracheae at each molt by a cement they produce.
Invertebrate trachea
The invertebrate trachea refers to the open respiratory system composed of spiracles, tracheae, and tracheoles that terrestrial arthropods have to transport metabolic gases to and from tissues....
of an insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
, part of the respiratory system
Respiratory system of insects
The respiratory system of insects is the means by which insects obtain oxygen from the air.-The Respiratory System:Air enters the respiratory systems of most insects through a series of external openings called spiracles. These external openings, which act as muscular valves in some insects, lead...
.
Tracheoles are about 1µm in diameter, and they convey oxygen to cells while providing a means for carbon dioxide to escape.
Tracheoles branch from the larger tracheae (which can be several mm in diameter) much like capillaries branch from arteries, or twigs from branches of a tree. This increases the surface area for gas exchange in the insect. Areas of intense metabolic activity, such as the digestive tract and flight muscles have very dense aggregations of tracheoles.
Though usually closely associated with cells, tracheoles physically penetrate only the flight muscle cells which have the highest oxygen demands.
Unlike the larger tracheae which are derived of ectodermal stem cells, tracheoles do not molt with the insect. Instead, they remain in place and fuse themselves to new tracheae at each molt by a cement they produce.