Describe the process of ventilation

Inspiration:-Diaphragm muscles contract, pulling the diaphragm downwards-External intercostal muscles contract pulling ribs upwards and outwards-Thoracic cavity increases in volume, causing pressure in lungs to drop below atmospheric pressure-Air moves down a pressure gradient into the lungs.Expiration:-Diaphragm muscles relax, diaphragm moves upwards into its dome shape-Internal intercostal muscles contract pulling ribs downwards and inwards-Thoracic cavity decreases in volume, increasing pressure in the lungs above atmospheric pressure.-Air moves along a pressure gradient out of the lungs-Elastic recoil of lung tissue forces air out