The trachea, bronchi and bronchioles form the tracheobronchial tree â a system of airways that allow passage of air into the lungs, where gas exchange occurs.he trachea marks the beginning of the tracheobronchial tree. It arises at the lower border of cricoid cartilage in the neck, as a continuation of the larynx. By Bibi Saint-Pol [CC BY-SA 3.0], via Wikimedia Commons. Fig 1.0 â Overview of the tracheobronchial tree.
While relative masses are nice if you want to compare protons, neutrons and electrons to one another, it doesn't tell you what the actual masses of these particles are. In kilograms, the masses are: Neutron = 1.6749286*10-27 kg.
The term nucleon refers to the particles found in the nucleus of an atom, namely protons and neutrons. A single hydrogen atom (one proton plus one electron) has a mass of 1.007825 amu.A single neutron has a mass of 1.008665 amu. Note that amu stands for atomic mass unit and is sometimes abbreviated with the symbol u.he total mass of the individual nucleons in an atom is always greater than the actual measured mass of the atom. The difference is called the mass defect. The mass defect of an atom corresponds to an amount of energy called the binding energy.