Respiration is the process by which organisms exchange gases with their environment, primarily involving the intake of oxygen (O2) and the release of carbon dioxide (CO2). In humans, respiration consists of two main processes: external respiration, which occurs in the lungs, and internal respiration, which occurs at the cellular level …
DeepakRajput 
Respiratory system
The respiratory system is a complex biological system in the human body responsible for the process of breathing. It includes the lungs, airways (such as the trachea and bronchi), and various muscles and structures that work together to facilitate the exchange of oxygen and carbon dioxide between the body and …
