Respiratory System

Cells in the human body require a steady supply of oxygen to survive. Oxygen is delivered to different parts of the body through the respiratory system. This system is comprised of the mouth, nose, windpipe, lungs and diaphragm.

Humans breath regularly to supply our bodies with oxygen and get rid of carbon dioxide (when we exhale).
Before the air reaches our lungs to be processed, it travels through your mouth and nose to go down your windpipe, which splits into two passages, one for each lung.
Each lung is like a spongey maze of tunnels called bronchi. The tunnels end in tiny air sacs called alveoli.  Your lungs stretch out when you breath to take in more air, and squish down to force all the air out, when you exhale. The muscle under your lungs is called the diaphragm. It acts like a trampoline, moving up and down as your breathe. 

Problems can arise with the respiratory system that can make it difficult to get enough oxygen. When a person has asthma, the bronchi in their lungs tightens up and restricts airflow.

Not every place has air humans can safely breath, so people carry their own air in portable tanks.
  • Firefighters need their own air supply as fire burns up oxygen and produces thick, toxic smoke.
  • Very high mountain tops are in a higher atmosphere with less oxygen for the body to process.
  • Space has no atmosphere and as such has no oxygen available for the human body to process.
  • Water contains oxygen, however its molecular structure makes it impossible for humans to use.
People can spend a few minutes underwater without breathing. The world record is six minutes however this is done with special training and safety measures.
You can take in between 0.5 to 3 litres of air with each breath. 

Further Reading