Respiratory System. Parts of respiratory system. Nasal cavity Oral cavity Trachea Bronchi Lung Alveoli Diaphragm. Functions of upper respiratory tract: nasal/oral cavities and trachea. Nose/Mouth:
Is the part of your body that flops down over the windpipe when you swallow to keep food from going into your lungs. Without your epiglottis, you would cough or choke every time you eat.