The diagram shows how the air pressure in the lungs changes during one full breathing cycle. The atmospheric pressure is $101\text{ kPa}$. At which point on the diagram do the ribs begin to be lowered?
- AA
- BB
- CC
- DD
Biology 0610 · IGCSE · Gas exchange in humans
The diagram shows how the air pressure in the lungs changes during one full breathing cycle. The atmospheric pressure is $101\text{ kPa}$. At which point on the diagram do the ribs begin to be lowered?