Question

why air is takenin through straw when diaphgram contracts in lungs working model. explain

Answer 1

Answer:

As the knotted balloon is pulled it creates more space inside the bottle. Air then comes down the straw and fills the balloon with some air to fill the space! When you let go of the knot the space no longer exists, so the air from the balloon is expelled making it deflate.  

Inside the lungs are a network of tubes which allow air to pass though. Air is warmed, moistened and filtered as it travels through the mouth and nasal passages. It then passes through the a network of tubes, eventually reaching tiny sacs called alveoli which are where gas exchange occurs.

Answer 2

Answer:

This increase the space in your chest cavity, and your lungs expand into it. The muscles between your ribs also help enlarge the chest cavity.