TASK. Copy to your notebook & finish the text.
When you inhale the diaphragm muscle
contracts / relaxes . This pulls the diaphragm
upwards / downwards . The intercostals
relax / contract and pull the ribcage
upwards / downwards . This
increases / decreases the volume inside your rib cage. The air now rushes
into / out of the lungs. This happens because the air pressure in the lungs is
lower / higher than the air pressure outside the body.
DONE ? Study 1.3 Like a pair of bellows