Life Processes

Living things undergo many life processes.   Some of these processes are breathing, excretion, defecation, response to stimuli and reproduction.

Humans Breathe

Humans need air to breathe.  when we breathe, we inhale (take in) and exhale (let out) air.  Our chest moves up and down.  The number of chest movement is the rate of breathing.  As we inhale, the chest rises outwards and upwards causing the chest to expand.  The air is taken in through the nose, down the windpipe into the lungs.  This air contains more oxygen.

As we exhale, the chest moves in causing the chest to contract.  The air inside the lungs then flows out from the lung to windpipe and then out through the nose.  This air contains more carbon dioxide.

The video is shown that the humans respiratory system.