Natsu with Lisanna, watching over their Dragon Egg. One day, Natsu found an egg in the forest east of Magnolia. Thinking it to be a Dragon Egg, Natsu took it to the guild and asked Makarov to make it hatch, but Makarov and Erza told him that he was the only one that could make the egg hatch; through love and care.
1 As a Decompression Chamberâ This is a hyperbaric chamber used by surface-supplied divers (commercial divers mostly) to make their decompression stops.  As Recompression chamberâ A hyperbaric chamber is used to treat or prevent patients suffering from decompression sickness.
The ventricles are the pumping chambers'. The atria are the receiving chambers of the heart. The ventricles, the right ventricle pumps blood to the lungs through the pulmonary artery (the only artery that carries deoxygenated blood). The left ventricle pumps blood to the rest of the body through the Aorta.