Final answer:
Particles larger than 10 micrometers are primarily trapped in the nasal passages by hairs and mucus, preventing them from reaching deeper parts of the respiratory system.
Step-by-step explanation:
The part of the respiratory system affected by particles larger than 10 micrometers (mcm) is the nasal passages. In the nasal cavity, protective mechanisms such as hairs and mucus are in place to trap small particles, this includes dust, dirt, and other potentially harmful particulate matter. These particles are trapped before they can reach the more sensitive parts of the respiratory system like the bronchioles or the alveoli, where gas exchange occurs. Therefore, larger particles do not typically penetrate deep into the lower respiratory tract.