Would be a 3 or 4 mark question and therefore would need 3 or 4 of these points in the answer to get full marks;external intercostal muscles and diaphragm contract (diaphragm flattens)resulting in the ripcage to move upwards and outwards increasing the volume in the thoracic cavity (or lung space/ chest cavity)thus resulting in a decreased pressure within this space compared to outside the lungs meaning air is drawn from outside into the lungs from an area of higher pressure to an area of lower pressure
1951 Views
See similar Physical Education A Level tutors