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.
What does the total number of protons and neutrons in the nucleus of an atom determine? This is the mass number of the atom, indicating relative mass of an isotope. For example uranium-235 (235U) is a lighter atom than uranium-238 (238U) because while both is â¦ otopes have 92 protons (the atomic number), the first has 3 fewer neutrons.