I think it's so your lungs can expand to help you breathe properly ? You may have to wait for some more answers to come through
bacteria are classified into 5 groups, spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes).
The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs and blood vessels. The muscles that power your lungs are also part of the respiratory system. These parts work together to move oxygen throughout the body and clean out waste gases like carbon dioxide.
Hope this help
Explanation:
a figure is need to be attached by this question because its not understandable hope you understood
