The trachea or windpipe is a flexible tube with rings of cartilage. The rings help provide support to the trachea and keep it open for air to pass through. Hence, it serves as a useful pathway for oxygen to get inside the body.

The epiglottis, located above the larynx, functions to prevent food and/or drinks from entering the windpipe. Injury to this may lead to the airways becoming narrow or blocked, which can potentially lead to respiratory failure.

The lungs help in delivering oxygen to all cells in the body. It protects the airways from harmful substances and removes waste every time we exhale, such as carbon dioxide.

References:
Epiglottitis – Symptoms and causes. (2020). Mayo Clinic; https://www.mayoclinic.org/diseases-conditions/epiglottitis/symptoms-causes/syc-20372227#:~:text=The%20epiglottis%20is%20a%20small,drink%20from%20entering%20your%20windpipe.

Respiratory System: Functions, Facts, Organs & Anatomy. (2020). Cleveland Clinic. https://my.clevelandclinic.org/health/articles/21205-respiratory-system

Trachea (Windpipe): Function and Anatomy. (2021). Cleveland Clinic. https://my.clevelandclinic.org/health/body/21828-trachea#:~:text=Your%20trachea’s%20main%20function%20is,oxygen%20to%20enter%20your%20body.