tracheole

CO diffuses out of the cell into the tracheole.

The sarcolemma is invaginated and can make contact with the tracheole carrying oxygen to the muscle fibre.

Taenidiae are circumferential thickenings of the cuticle inside a trachea or tracheole in an insect's respiratory system.

During the fourth instar, cells from the epithelium of this trachea become greatly enlarged extend into the cavity of the wing bud, with each cell having developed a closely coiled tracheole.