The occlusion of the y-port could cause laryngeal, or a trauma to the tracheal mucosa. Any foreign object that touches the air passages, especially with an occluded tracheotomy tube can damage or block the airways. It is important to do this procedure with care.
Mendel disproved the blending theory of genetics when he cross pollinated tall and short pea plants and the offspring were either tall or short, not medium like the blending theory of genetics suggests.